Add SecurityContext to restore-helper

[reasonerjt]

This commit adds SecurityContext which complies with "restricted" level per Pod Security Standards

Fixes #8229

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

Attention: Patch coverage is 72.72727% with 6 lines in your changes missing coverage. Please review.

Project coverage is 59.03%. Comparing base (2e5df85) to head (4b7f931).
Report is 8 commits behind head on main.

Files with missing lines	Patch %	Lines
pkg/restore/actions/pod_volume_restore_action.go	72.72%	5 Missing and 1 partial ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #8491      +/-   ##
==========================================
+ Coverage   58.96%   59.03%   +0.07%     
==========================================
  Files         368      369       +1     
  Lines       39024    39074      +50     
==========================================
+ Hits        23009    23067      +58     
+ Misses      14552    14545       -7     
+ Partials     1463     1462       -1     

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