use newGR instead of groupResource after apiversion convert

[AlbeeSo]

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Please add a summary of your change

When try restore ingresses.extensions in Kubernetes 1.30， restore will be PartiallyFailed as ingresses.extensions is not supported any more. Our plugin try to convert the apiVersion in these cases, which will change the group of the item. So I think groupResource should be replaced by newGR after plugin has finished?

Does your change fix a particular issue?

Fixes #(issue)

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• Accepted the DCO. Commits without the DCO will delay acceptance.
• Created a changelog file or added /kind changelog-not-required as a comment on this pull request.
• Updated the corresponding documentation in site/content/docs/main.

[AlbeeSo]

/kind changelog-not-required

[codecov]

Codecov Report

Attention: Patch coverage is 50.00000% with 5 lines in your changes missing coverage. Please review.

Project coverage is 59.23%. Comparing base (49eab81) to head (c2192a7).
Report is 249 commits behind head on main.

Files with missing lines	Patch %	Lines
pkg/restore/restore.go	50.00%	3 Missing and 2 partials ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #8199      +/-   ##
==========================================
+ Coverage   58.67%   59.23%   +0.55%     
==========================================
  Files         345      367      +22     
  Lines       28743    30710    +1967     
==========================================
+ Hits        16866    18190    +1324     
- Misses      10448    11065     +617     
- Partials     1429     1455      +26     

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