Checkbox based CI workflow

[mwestphal]

Describe your changes

• Add a PULL_REQUEST_TEMPLATE.md
• Add a linux_fast CI
• Add a checkbox checking logic to detect which CI to run

Note: If someone add a checked checkbox and put "Full CI" next to it anywhere in the PR description , CI will run even if not intended. That seems fine to me.

Issue ticket number and link if any

Related to: #194

Checklist for finalizing the PR

• I have performed a self-review of my code
• I have added tests for new features and bugfixes
• I have added documentation for new features
• If it is a modifying the libf3d API, I have updated bindings
• If it is a modifying the default versions, I have updated timestamp

Continuous integration

Please check the checkbox of the CI you want to run, then push again on your branch.

• Style checks
• Fast CI
• Coverage cached CI
• Analysis cached CI
• WASM CI
• Android CI
• macOS Intel cached CI
• macOS ARM cached CI
• Windows cached CI
• Linux cached CI
• Other cached CI

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 95.90%. Comparing base (acc053c) to head (a7800ff).
Report is 8 commits behind head on master.

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #2177      +/-   ##
==========================================
+ Coverage   95.86%   95.90%   +0.03%     
==========================================
  Files         127      127              
  Lines       11060    11090      +30     
==========================================
+ Hits        10603    10636      +33     
+ Misses        457      454       -3     

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[Meakk]

Looks good. Let's see if it works well in practice and adjust it if needed.