[cherry-pick][1.13]Check whether the VolumeSnapshot's source PVC is nil before using it

[blackpiglet]

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[codecov]

Codecov Report

Attention: Patch coverage is 40.00000% with 3 lines in your changes are missing coverage. Please review.

Project coverage is 62.04%. Comparing base (6499444) to head (40eed65).

Files	Patch %	Lines
internal/volume/volumes_information.go	0.00%	2 Missing and 1 partial ⚠️

Additional details and impacted files

@@               Coverage Diff                @@
##           release-1.13    #7789      +/-   ##
================================================
+ Coverage         61.66%   62.04%   +0.37%     
================================================
  Files               262      262              
  Lines             28450    22428    -6022     
================================================
- Hits              17545    13915    -3630     
+ Misses             9667     7274    -2393     
- Partials           1238     1239       +1     

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