[Fixes #ISSUE_11995] GNIP 99: Implement a CRUD REST API for users

[mattiagiupponi]

Implementation of the user CRUD api described in #11995
cc: @RegisSinjari

Checklist

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⚠️ GitGuardian has uncovered 4 secrets following the scan of your pull request.

Please consider investigating the findings and remediating the incidents. Failure to do so may lead to compromising the associated services or software components.

🔎 Detected hardcoded secrets in your pull request

GitGuardian id	GitGuardian status	Secret	Commit	Filename
9702486	Triggered	Generic Password	a411232	geonode/people/tests.py	View secret
9702486	Triggered	Generic Password	a411232	geonode/people/tests.py	View secret
9768717	Triggered	Username Password	a411232	geonode/people/tests.py	View secret
9705160	Triggered	Username Password	a411232	geonode/base/api/tests.py	View secret

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[mattiagiupponi]

Doc PR provided by @RegisSinjari available GeoNode/documentation#302

[giohappy]

@RegisSinjari please check the failing test

[codecov]

Codecov Report

Merging #12072 (f559c65) into master (023761d) will increase coverage by 0.36%.
Report is 33 commits behind head on master.
The diff coverage is 99.80%.

Additional details and impacted files

@@            Coverage Diff             @@
##           master   #12072      +/-   ##
==========================================
+ Coverage   63.67%   64.04%   +0.36%     
==========================================
  Files         867      867              
  Lines       52664    53173     +509     
  Branches     6600     6650      +50     
==========================================
+ Hits        33535    34053     +518     
+ Misses      17610    17591      -19     
- Partials     1519     1529      +10