Y24-475 [PR] [BUG] Improve integration suite UAT actions error message

[yoldas]

Closes #

Changes proposed in this pull request

• Add validations to the UAT actions that are most likely to raise exceptions at the beginning of WIP pipelines, in order to prevent misleading responses
  • 500 Internal Server Error, because of null access
  • 404 Not Found Error, because of ActiveRecord::RecordNotFound exception
• Add error messages for the non-existent records, so they are properly serialised into JSON by the UAT action controller and added to the response
  • 422 Unprocessable Content

See also command line examples in the story comment sanger/General-Backlog-Items#477 (comment)

Instructions for Reviewers

[All PRs] - Confirm PR template filled
[Feature Branches] - Review code
[Production Merges to main]
    - Check story numbers included
    - Check for debug code
    - Check version

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 89.41%. Comparing base (644d4c1) to head (e324a76).
Report is 19 commits behind head on develop.

Additional details and impacted files

@@             Coverage Diff             @@
##           develop    #4596      +/-   ##
===========================================
+ Coverage    89.28%   89.41%   +0.12%     
===========================================
  Files         1407     1407              
  Lines        30244    30332      +88     
===========================================
+ Hits         27003    27121     +118     
+ Misses        3241     3211      -30     

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[BenTopping]

Good comprehensive error messaging and test coverage, nice work.

Just wondering about combining presence validation and existing record validation into one in some places so we don't perform multiple checks.

[BenTopping]

Looks good to me.