[Fixes #13250] Enable the group managers to edit their group's resources

[Gpetrak]

This PR was created according to this issue: #13250

Checklist

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• There is a ticket in https://github.com/GeoNode/geonode/issues describing the issue/improvement/feature (a notable exemption is, changes not visible to end-users)
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[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 72.67%. Comparing base (2825f29) to head (ec65d9c).
Report is 8 commits behind head on master.

Additional details and impacted files

@@            Coverage Diff             @@
##           master   #13251      +/-   ##
==========================================
+ Coverage   72.64%   72.67%   +0.03%     
==========================================
  Files         917      917              
  Lines       52641    52688      +47     
  Branches     6055     6059       +4     
==========================================
+ Hits        38239    38289      +50     
+ Misses      12836    12832       -4     
- Partials     1566     1567       +1     

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