ci: don't cancel in-progress jobs in matrix if others fail

[G-Rath]

This PR contains a:

• bugfix
• new feature
• code refactor
• test update
• typo fix
• metadata update

Motivation / Use-Case

Matrixes "fail fast" by default, which can be annoying as failures in linting and the test suite by the time a pull request are technically expected to be because of one specific dimension (e.g. an os, since most people don't develop on multiple os's at the same time) - so this disables that :)

Breaking Changes

Not a breaking change

Additional Info

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 93.93%. Comparing base (31789cc) to head (701f77a).
Report is 12 commits behind head on master.

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #1213      +/-   ##
==========================================
- Coverage   94.44%   93.93%   -0.52%     
==========================================
  Files           3        3              
  Lines         360      412      +52     
  Branches      132      155      +23     
==========================================
+ Hits          340      387      +47     
- Misses         18       23       +5     
  Partials        2        2              

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[evenstensberg]

I think fail fast is good. When the CI fails, you'll most likely have to rerun the jobs anyway

[G-Rath]

Yes, but you're more likely to have to re-run it more because you might have os-specific failures - for example I won't know if #1211 is going to pass on any OSs because the macOS job failed; now that #1215 is landed that should be unblocked but now I'll just learn if any-but-not-all of the OSs are passing (and repeat until all jobs are passing...)

Ultimately up to you though - please do close this PR if you'd still prefer to keep fail-fast enabled :)

[evenstensberg]

I think we will close this, but thank you so much for the contribution, appreciate you!