It should be possible to specify multiple new has_many record links

[faucct]

No description provided.

[codecov]

Codecov Report

Merging #5367 into master will increase coverage by <.01%.
The diff coverage is 100%.

@@            Coverage Diff             @@
##           master    #5367      +/-   ##
==========================================
+ Coverage   98.32%   98.33%   +<.01%     
==========================================
  Files         294      294              
  Lines       11015    11036      +21     
==========================================
+ Hits        10831    10852      +21     
  Misses        184      184

Impacted Files	Coverage Δ
lib/active_admin/form_builder.rb	100% <100%> (ø)	⬆️
spec/unit/form_builder_spec.rb	99.29% <100%> (+0.01%)	⬆️

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[zorab47]

Can you describe the use case and provide more background on this change?

[faucct]

We use this feature to make it possible to create STI records: instead of exposing #type select input each subclass has its own "Add record" link with a customized form which could have more or less inputs. Persisted records also get customized forms.
Here is another usecase – #5309