Add backend tests covering full entitlement import flow

[johniak]

AB#287467

Please read the ticket to verify if it is correctly done.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 92.26%. Comparing base (6912971) to head (e2013d8).
⚠️ Report is 16 commits behind head on develop.

Additional details and impacted files

@@             Coverage Diff             @@
##           develop    #5908      +/-   ##
===========================================
+ Coverage    92.25%   92.26%   +0.01%     
===========================================
  Files          494      494              
  Lines        34349    34361      +12     
  Branches      3602     3603       +1     
===========================================
+ Hits         31689    31704      +15     
+ Misses        1911     1908       -3     
  Partials       749      749              

Flag	Coverage Δ
e2e	52.63% <ø> (-0.02%)	⬇️
unit	91.97% <ø> (+0.01%)	⬆️

Flags with carried forward coverage won't be shown. Click here to find out more.

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.

🚀 New features to boost your workflow:

• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.
• 📦 JS Bundle Analysis: Save yourself from yourself by tracking and limiting bundle sizes in JS merges.