Fix deprecation warnings regarding collections.abc

[tirkarthi]

Fixes #613

Description of the Change

• Fix DeprecationWarning over usage of collections instead of collections.abc

Checklist

• PR only contains one change (considered splitting up PR)
• unit-test added
• documentation updated
• CHANGELOG.md updated (only for user relevant changes)
• author name in AUTHORS

The PR doesn't seem to have user impacting changes. Let me know if these need to be updated.

Thanks.

[codecov]

Codecov Report

Merging #624 into master will increase coverage by 0.01%.
The diff coverage is 100%.

@@            Coverage Diff             @@
##           master     #624      +/-   ##
==========================================
+ Coverage   95.65%   95.66%   +0.01%     
==========================================
  Files          55       55              
  Lines        2856     2863       +7     
==========================================
+ Hits         2732     2739       +7     
  Misses        124      124

Impacted Files	Coverage Δ
rest_framework_json_api/relations.py	85.5% <100%> (+0.21%)	⬆️
rest_framework_json_api/renderers.py	87.5% <100%> (+0.16%)	⬆️

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[codecov]

Codecov Report

Merging #624 into master will increase coverage by <.01%.
The diff coverage is 100%.

@@            Coverage Diff             @@
##           master     #624      +/-   ##
==========================================
+ Coverage   95.65%   95.66%   +<.01%     
==========================================
  Files          55       56       +1     
  Lines        2856     2861       +5     
==========================================
+ Hits         2732     2737       +5     
  Misses        124      124

Impacted Files	Coverage Δ
rest_framework_json_api/compat.py	100% <100%> (ø)
rest_framework_json_api/relations.py	85.29% <100%> (ø)	⬆️
rest_framework_json_api/renderers.py	87.37% <100%> (+0.04%)	⬆️

---

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Δ = absolute <relative> (impact), ø = not affected, ? = missing data
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[sliverc]

Thanks for working on this.

I would prefer if we could move those imports into a compat.py as DRF does This way we will find the deprecation fixes again in the future in case we can delete it again.

I think a CHANGELOG entry will also be needed below Fixed as a deprecation warning fix is user facing e.g. for users who turn deprecation warnings into errors.

[tirkarthi]

Currently there is no compat.py. Do you want me to create one and move my changes there?

[sliverc]

yes best create one. This way we follow how DRF handles such issues.

[tirkarthi]

I have modified my PR to use compat.py and also added a note on Changelog.

[sliverc]

Looks good. Thanks!