Update extension of volume policies design

[shubham-pampattiwar]

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Update extension of volume policies design Remove requirement of snapshotVolumes flag for snapshot action

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• [x] Accepted the DCO. Commits without the DCO will delay acceptance.
• [x] Created a changelog file or added /kind changelog-not-required as a comment on this pull request.
• [ ] Updated the corresponding documentation in site/content/docs/main.

[codecov[bot]]

Codecov Report

All modified and coverable lines are covered by tests :white_check_mark:

Project coverage is 58.67%. Comparing base (a0b7382) to head (2adb0a6).

Additional details and impacted files

```diff @@ Coverage Diff @@ ## main #7803 +/- ## ======================================= Coverage 58.67% 58.67% ======================================= Files 345 345 Lines 28739 28739 ======================================= Hits 16862 16862 Misses 10448 10448 Partials 1429 1429 ```

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[Lyndon-Li]

@shubham-pampattiwar @blackpiglet I think we should add more details about how volumePolicy works with --snapshotVolume flag in the design, so as to reflect the changes in PR #7794.

[blackpiglet]

Because #7794 already included the design change of VolumePolicy, we can close this PR.

[reasonerjt]

@shubham-pampattiwar I'm closing this one, please ping me on slack if there's different opinion.