Create a GHA reusable workflow rather than cloning the gha dist everywhere

[aspark21]

Every time there are changes to the gha.dist.yml we have to copy it across 50 repos and reconcile the repo specific config (matrix, additional plugins) with the template. It's quite a faff to have to keep doing
https://github.com/moodlehq/moodle-plugin-ci/blob/main/gha.dist.yml

I wonder wether we could move this around so there is a github actions reusable workflow in the moodle-plugin-ci repo that is kept up to date within here, and in our plugin repos we can just call this reusable workflow, while having the matrix & additional plugins specifically setup thus effortlessly always keeping up to date with all of the improvements to moodle-plugin-ci

Happy to work on it if there is appetite for a pull request.

[kabalin]

Hi @aspark21, that is great suggestion. It would be good to have it as GH action, so PR is welcomed :)

For inspiration, this is a snippet by @andrewnicols outlining how this may look like:

- name: Plugin CI Checks
  uses: moodlehq/moodle-plugin-ci@v3
  with:
    moodle-branch: ${{ matrix.moodle-branch }}
    DB: ${{ matrix.database }}
    # All tests are run by default unless otherwise specified, for example:
    lint: false
    # Or arguments may be specified, for example:
    phpmd:
      args: --max-warnings 0
    behat:
      profile: chrome
      suite: classic

[stronk7]

Just noting that, if we go the GH Action (vs reusable workflow) way, there is also #53, created long ago.