Add action for Hook Documentation Generation

[puntope]

Changes proposed in this Pull Request:

This PR creates an Action for generating PHP Hooks documentation when PHP files change.

It will commit a README.md in src/Hooks/README.md

Screenshots

Detailed test instructions:

1. Verify how the README.md has been generated in src/HOOKS/README.md
2. Check in the file diff the links working and it's most likely as it was before.
3. See the workflow is triggered on release branches. Release/hook docs test #2064

Additional details:

Changelog entry

Dev - Add Action for Hooks Documentation Generator

[puntope]

At first, this Workflow was triggered when a push event happened with some PHP files.

After discussion with the team, now we changed the trigger to only run on release branches.

You can see the trigger in another release branch here: #2064

[mikkamp]

Thanks for the changes they seem to be working well as far as I can see. The workflow is triggered and commits a new version of src/Hooks/README.md when a release branch is update.

As far as I understand we also want to maintain only one script within our grow repo. So the script bin/HooksDocsGenerator.php can be removed.

I just left a few minor comments but this should be pretty much good to go, so I'll mark the PR as approved.

[mikkamp]

The push and pull_request (with the PHP filter), look fine to me. But I was wondering if it would do any harm to also allow us to run this manually, like here. It's not going to effect our automated flows, and will make it easier if we ever want to run it manually.

[puntope]

I implemented this suggestions

[mikkamp]

What about the main plugin file google-listings-and-ads.php? Is this strictly a list of directories or does it support single files as well?

It so happens we don't have any hooks there now, but considering we want to use it for other extensions the script should be flexible enough to include the main plugin file. If that's not possible then can we log an issue in the Grow repo that this should be fixed?

[puntope]

Seems like its possible as internally it uses Finder()->path()

You can see it here in a test when I added gla_test_action inside the main plugin file.

https://github.com/woocommerce/google-listings-and-ads/actions/runs/5902917550/job/16011805311