Add VolumeSnapshotContent into the RIA and the mustHave resource list.

[blackpiglet]

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Does your change fix a particular issue?

Fixes #8904

Please indicate you've done the following:

• Accepted the DCO. Commits without the DCO will delay acceptance.
• Created a changelog file (make new-changelog) or comment /kind changelog-not-required on this PR.
• Updated the corresponding documentation in site/content/docs/main.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 59.56%. Comparing base (670c870) to head (3a30c7f).
Report is 1 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #8924      +/-   ##
==========================================
+ Coverage   59.55%   59.56%   +0.01%     
==========================================
  Files         370      370              
  Lines       40257    40267      +10     
==========================================
+ Hits        23977    23987      +10     
  Misses      14778    14778              
  Partials     1502     1502              

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