Snapshot delete error

[kei-git]

Issue/Feature Description:
If endusers change the name of NetApp fileshare after taking a snapshot of that fileshare, they cannot delete the snapshot with some error log.

Why this issue to fixed / feature is needed(give scenarios or use cases):
Even if endusers change the name, they should be able to delete it.

How to reproduce, in case of a bug:

Other Notes / Environment Information: (Please give the env information, log link or any useful information for this issue)

# tail -f /var/log/opensds/osdslet.ERROR

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E0923 02:38:07.933130 7114 filesharecontroller.go:201] delete file share snapshot failed in file share controller:rpc error: code = Unknown desc = error deleting snapshot: API status: failed, Reason: Volume name: The first character must be a letter or underscore., Code: 13001
E0923 02:38:07.933187 7114 controller.go:1077] error occurred in controller module when delete file share snapshot: rpc error: code = Unknown desc = error deleting snapshot: API status: failed, Reason: Volume name: The first character must be a letter or underscore., Code: 13001
E0923 02:38:07.934713 7114 grpcserver.go:92] call function 'github.com/sodafoundation/controller/pkg/controller.(*Controller).DeleteFileShareSnapshot-fm' failed: rpc error: code = Unknown desc = error deleting snapshot: API status: failed, Reason: Volume name: The first character must be a letter or underscore., Code: 13001