Test matrix of ruby/rails versions on different Databases

[cpfergus1]

Summary

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[codecov]

Codecov Report

Merging #4652 (1e2df19) into master (29da36c) will decrease coverage by 0.43%.
The diff coverage is n/a.

❗ Current head 1e2df19 differs from pull request most recent head a28d718. Consider uploading reports for the commit a28d718 to get more accurate results

@@            Coverage Diff             @@
##           master    #4652      +/-   ##
==========================================
- Coverage   86.02%   85.59%   -0.44%     
==========================================
  Files         571      571              
  Lines       14611    14629      +18     
==========================================
- Hits        12569    12521      -48     
- Misses       2042     2108      +66     

Impacted Files	Coverage Δ
...pp/models/spree/taxon/active_storage_attachment.rb	0.00% <0.00%> (-100.00%)	⬇️
...oncerns/spree/active_storage_adapter/attachment.rb	0.00% <0.00%> (-92.69%)	⬇️
...erns/spree/active_storage_adapter/normalization.rb	41.17% <0.00%> (-47.06%)	⬇️
...pp/models/concerns/spree/active_storage_adapter.rb	67.79% <0.00%> (-23.73%)	⬇️
...pp/models/spree/image/active_storage_attachment.rb	83.33% <0.00%> (-16.67%)	⬇️
core/lib/spree/rails_compatibility.rb	63.63% <0.00%> (-3.04%)	⬇️
core/lib/spree/testing_support/dummy_app.rb	94.73% <0.00%> (-2.64%)	⬇️
core/app/models/spree/credit_card.rb	96.82% <0.00%> (+0.05%)	⬆️
...ore/app/models/spree/image/paperclip_attachment.rb	91.66% <0.00%> (+41.66%)	⬆️
...ore/app/models/spree/taxon/paperclip_attachment.rb	100.00% <0.00%> (+100.00%)	⬆️

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[elia]

Early review, hope it's useful

[elia]

nit: I think could accept just 7.0 and the ~> be added when setting the ENV var below, this would make it look a bit more generic and also prettify the generated job name

[elia]

Should this parameter be named database instead?
Probably just me but I had to read twice in order to understand the reference to executors

[elia]

Should these be moved up together with net-http so they can share the guard and comment?

[elia]

Replaced by #4666