fix: [AAP-40152] solve 500 error when project is updated

[hsong-rh]

https://issues.redhat.com/browse/AAP-40152

Remove created_by and modified_by from the updating payload data. These two fields are updated when they are saved to DB

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud

[codecov-commenter]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 93.59%. Comparing base (5bee2bf) to head (c2384be).

@@            Coverage Diff             @@
##             main    #1211      +/-   ##
==========================================
- Coverage   93.59%   93.59%   -0.01%     
==========================================
  Files         270      270              
  Lines       15561    15559       -2     
==========================================
- Hits        14565    14563       -2     
  Misses        996      996              

Flag	Coverage Δ
unit-int-tests-3.11	93.53% <ø> (-0.01%)	⬇️
unit-int-tests-3.12	93.59% <ø> (-0.01%)	⬇️

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Files with missing lines	Coverage Δ
src/aap_eda/api/serializers/project.py	93.00% <ø> (-0.14%)	⬇️