[Fixes #11494] Implement relations between resources

[etj]

Implements changes described in #11494

Checklist

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[codecov]

Codecov Report

Merging #11565 (f5f18b1) into master (8913d8e) will increase coverage by 0.01%.
The diff coverage is 91.56%.

❗ Current head f5f18b1 differs from pull request most recent head 11faa5e. Consider uploading reports for the commit 11faa5e to get more accurate results

Additional details and impacted files

@@            Coverage Diff             @@
##           master   #11565      +/-   ##
==========================================
+ Coverage   62.12%   62.13%   +0.01%     
==========================================
  Files         869      871       +2     
  Lines       51993    51987       -6     
  Branches     6492     6495       +3     
==========================================
+ Hits        32300    32302       +2     
+ Misses      18139    18136       -3     
+ Partials     1554     1549       -5