CI: general workflow improvements

[jorgepiloto]

This pull-request allows the CI/CD pipelines to operate on a label-based approach. Main advantage is that the self-hosted runner workload gets reduced.

The CI/CD identifies which files have been modified and adds some default tags. These trigger only the required jobs. For example, if a developer adds a new example, there is no need to run the tests. Only the example should be executed.

On top of this, authorized developers in this repository can freely choose the tags in the PR, to run desired workflows on demand.

• [x] Split between ci_cd_pr.yml, ci_cd_main.yml, ci_cd_night.yml, and ci_cd_release.yml
• [x] Tests have been grouped in matrix jobs. This removes code duplication while still providing custom configuration

Pull-request workflow

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[codecov[bot]]

Codecov Report

All modified and coverable lines are covered by tests :white_check_mark:

Project coverage is 36.80%. Comparing base (3539828) to head (c302aa9). Report is 8 commits behind head on main.

Additional details and impacted files

```diff @@ Coverage Diff @@ ## main #4796 +/- ## =========================================== - Coverage 82.66% 36.80% -45.86% =========================================== Files 117 117 Lines 54159 54151 -8 =========================================== - Hits 44770 19931 -24839 - Misses 9389 34220 +24831 ```