[Fixes #11995 Implement POST and PATCH methods for the User API

[mattiagiupponi]

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[codecov]

Codecov Report

Merging #12011 (26c940f) into ISSUE_11995 (023761d) will increase coverage by 0.13%.
The diff coverage is 99.46%.

Additional details and impacted files

@@               Coverage Diff               @@
##           ISSUE_11995   #12011      +/-   ##
===============================================
+ Coverage        63.67%   63.81%   +0.13%     
===============================================
  Files              867      867              
  Lines            52664    52843     +179     
  Branches          6600     6609       +9     
===============================================
+ Hits             33535    33720     +185     
+ Misses           17610    17598      -12     
- Partials          1519     1525       +6     

[mattiagiupponi]

this is a good way to re-use the already existing IsOwnerOrAdmin we decided to use this class, because the check on the User object was already present. We just update the check to be sure that the users that belong to the same group can see each other