Look for a VolumeGroupSnapshotClass when getting the class of a VolumeGroupSnapshot

[leonardoce]

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 looking for the name of the CSI driver to use for a volume group snapshot, we were looking for a VolumeSnapshotClass instead of a VolumeGroupSnapshotClass. This made the VolumeGroupSnapshot fail when there is no such VolumeGroupSnapshotClass.

Which issue(s) this PR fixes:

Fixes #

Special notes for your reviewer:

Does this PR introduce a user-facing change?:

Look for a VolumeGroupSnapshotClass instead of a VolumeSnapshotClass when getting metrics data for VolumeGroupSnapshot metrics.

[Madhu-1]

/lgtm
/assign @xing-yang

[leonardoce]

I rebased it over the latest master

[Madhu-1]

/assign @xing-yang for approval

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/assign @xing-yang for approval

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[Madhu-1]

/lgtm

[xing-yang]

/approve

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: leonardoce, Madhu-1, xing-yang

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