Added model multiple list filtering through ","

[bubaley]

Comma separating value in ModelMultipleChoiceField to allow multiple objects to be passed in one query parameter.

[codecov-commenter]

Codecov Report

Merging #1492 (972ff5a) into main (dbc69e7) will decrease coverage by 0.07%.
The diff coverage is 83.33%.

@@            Coverage Diff             @@
##             main    #1492      +/-   ##
==========================================
- Coverage   99.44%   99.37%   -0.08%     
==========================================
  Files          15       15              
  Lines        1270     1276       +6     
==========================================
+ Hits         1263     1268       +5     
- Misses          7        8       +1     

Impacted Files	Coverage Δ
django_filters/fields.py	99.43% <83.33%> (-0.57%)	⬇️

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[eloi-martinez-qida]

What does this pr need to be merged? if anything?

[carltongibson]

CI failure. No tests, no docs. No discussion about whether it's a desired feature. (For a start).

[eloi-martinez-qida]

I see, i would say it's a desired feature (at least for me), it would make calling it similar to the Infilter, also, i don't find it very natural tu use the same query key multiples times (in the request).
Maybe it could be parametrized with an optinal argument.