Utilize a standardized ClusterInventory API for the automatic import of clusters into ArgoCD

[iam-veeramalla]

Is your feature request related to a problem? Please describe.
There are several community multicluster platforms that have the concept of a cluster inventory or cluster registry. When a user installs the argocd-operator, it would be beneficial to have an option that enables automatic importing of all these clusters into ArgoCD. This way, users wouldn't have to add them manually one by one.

Describe the solution you'd like
The k8s multicluster-SIG community is working on a plan to introduce a standardized ClusterInventory API. This API aims to facilitate the interaction between various multicluster platforms and third-party consumers like ArgoCD. By adopting this new API, the ArgoCD operator will be able to automatically import clusters into ArgoCD without the need to reference other third-party APIs.

Describe alternatives you've considered
Although scripting the import of clusters is possible, it's not user friendly.

Additional context
Cluster Inventory API

[mikeshng]

The KEP has been merged. We are working on a CRD implementation in kubernetes-sigs/cluster-inventory-api#6 . There are other discussions that will make it easier for ArgoCD to consume this new API such as storing endpoint access info: doc and kubernetes/enhancements#4579 that needs to be flushed out. Please feel free to take a look. Thanks.

CC @jannfis