Add support for github actions to moodle.git

Notes: dev is required for testing this (git access, integration.git as remote and github clone of moodle.git) this must be done for all branches. Instructions: Ensure that you've github actions enabled for your moodle clone: Go to https://github.com/YOURUSER/moodle/settings/actions Verify that "Allow all actions" is ticked. Pull the corresponding branch from integration.git to local branch with easy to remember name (actions-master, actions-311...). Push all those branches to github. Go to your https://github.com/YOURUSER/moodle/actions URL, there should be a workflow for each of the pushed branches. Verify they run grunt and a couple of phpunit jobs. Verify they end ok / green / passing Don't forget to remove the branches from your repos after the test. Also, verify that the badges in this issue (this is the only issue currently showing them) are linking to a workflow run, exactly to the last one for a branch. To do this you can: go to https://github.com/stronk7/moodle/actions then look/filter for branch: MDL-70276 _35 for example. that will show all the runs performed against the 35 branch of this issue. Verify that the 1st element in the list, the more recent one, matches the badge URL shown here. Run locally php .github/workflows/config-template.php and verify that it dies silently and nothing is executed / output. Run in your browser http://your.moodle.site/path/to/.github/workflows/config-template.php and verify that it dies silently and nothing is executed / output.