[UI][IMPROVEMENT] Improve the UX of updating danger zone settings

[github-actions]

make corresponding UI changes for #8070

cc @longhorn/dev-ui

[a110605]

Waiting for longhorn / longhorn-manager PRs merge first.

• crd: introduce the field applied in setting #8424
• fix(setting): UX of updating danger zone settings longhorn-manager#2728

[a110605]

After synced with @mantissahz, he will add applied field for all danger zone settings to indicate they are applied or not.

Settings page can add some descriptions in danger zone block according to the danger-zone document and show those unapplied (applied=false) setting in notification or somewhere in UI to let user know.

[mantissahz]

related: longhorn/longhorn-manager#2820

[longhorn-io-github-bot]

Pre Ready-For-Testing Checklist

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