fix: do not emit VolumeResizeFailed on conflict while trying to set FileSystemResizeRequired or VolumeResizeSuccess

[jakobmoellerdev]

What type of PR is this?

Uncomment only one /kind <> line, hit enter to put that in a new line, and remove leading whitespaces from that line:

/kind api-change
/kind bug
/kind cleanup
/kind design
/kind documentation
/kind failing-test
/kind feature
/kind flake

What this PR does / why we need it:

When doing a CSI call to ExpandVolume, external-resizer tries to update the PVC with FilesystemResizeRequired . Usually this works fine, however, in case of a PVC conflict, the external-resizer emits an event on the PVC with VolumeResizeFailed. This event is misleading because the Resize did not actually fail, merely the update to the PVC as requiring the Resize failed. Since this will almost always (unless we face endless races) recover gracefully for conflicts, we should avoid sending the event in this case, and rather recover normally. The logs will still emit a sync failure so admins will still be able to notice races, the event will just no longer be published.

Here is an example we collected during test runs in the downstream CSI driver TopoLVM:

│ Name:             topo-pvc.17c9d3a398b23494                                                                                                                                                                                                                                   │
│ Namespace:        e2etest-xgwhounmef                                                                                                                                                                                                                                          │
│ Labels:           <none>                                                                                                                                                                                                                                                      │
│ Annotations:      <none>                                                                                                                                                                                                                                                      │
│ API Version:      v1                                                                                                                                                                                                                                                          │
│ Count:            1                                                                                                                                                                                                                                                           │
│ Event Time:       <nil>                                                                                                                                                                                                                                                       │
│ First Timestamp:  2024-04-26T12:17:12Z                                                                                                                                                                                                                                        │
│ Involved Object:                                                                                                                                                                                                                                                              │
│   API Version:       v1                                                                                                                                                                                                                                                       │
│   Kind:              PersistentVolumeClaim                                                                                                                                                                                                                                    │
│   Name:              topo-pvc                                                                                                                                                                                                                                                 │
│   Namespace:         e2etest-xgwhounmef                                                                                                                                                                                                                                       │
│   Resource Version:  1509                                                                                                                                                                                                                                                     │
│   UID:               d447f77e-fcb4-49f7-acea-73d26b524755                                                                                                                                                                                                                     │
│ Kind:                Event                                                                                                                                                                                                                                                    │
│ Last Timestamp:      2024-04-26T12:17:12Z                                                                                                                                                                                                                                     │
│ Message:             Mark PVC "e2etest-xgwhounmef/topo-pvc" as file system resize required failed: can't patch status of  PVC e2etest-xgwhounmef/topo-pvc with Operation cannot be fulfilled on persistentvolumeclaims "topo-pvc": the object has been modified; please apply │
│  your changes to the latest version and try again                                                                                                                                                                                                                             │
│ Metadata:                                                                                                                                                                                                                                                                     │
│   Creation Timestamp:  2024-04-26T12:17:12Z                                                                                                                                                                                                                                   │
│   Resource Version:    1524                                                                                                                                                                                                                                                   │
│   UID:                 0199e840-7f9a-422e-b44e-c3014f8f5c0e                                                                                                                                                                                                                   │
│ Reason:                VolumeResizeFailed 

Which issue(s) this PR fixes:

Fixes #

Special notes for your reviewer:

Does this PR introduce a user-facing change?:

When encountering a resource conflict while attempting set `FileSystemResizeRequired` or `VolumeResizeSuccess`, there is no longer a `VolumeResizeFailed` event emitted.

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[k8s-ci-robot]

Hi @jakobmoellerdev. Thanks for your PR.

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[jsafrane]

/ok-to-test

[jsafrane]

/lgtm
/approve

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: jakobmoellerdev, jsafrane

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