[#2507] Fixed and added test for 'django-admin-index' fixture

[Bartvaderkin]

I think the mechanism wasn't broken, it just errored on bad data (there was a content-type in there that was removed).

Note it listens to the post-migrate signal (eg: not application startup). If we runt this on application start it would run for every test and management command as well (and it deletes and re-creates all the records)

Taiga: https://taiga.maykinmedia.nl/project/open-inwoner/us/2482

[codecov-commenter]

Codecov Report

Attention: Patch coverage is 55.55556% with 4 lines in your changes are missing coverage. Please review.

Project coverage is 95.20%. Comparing base (9347350) to head (0b8e598).

Files	Patch %	Lines
src/open_inwoner/accounts/apps.py	55.55%	4 Missing ⚠️

Additional details and impacted files

@@             Coverage Diff             @@
##           develop    #1220      +/-   ##
===========================================
- Coverage    95.21%   95.20%   -0.01%     
===========================================
  Files          968      968              
  Lines        35256    35261       +5     
===========================================
+ Hits         33568    33571       +3     
- Misses        1688     1690       +2     

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[Bartvaderkin]

@pi-sigma In hindsight I don't think the issue was the signal, just the bad data, and running this on application startup is not actually desirable.

[pi-sigma]

Seems reasonable