ci: use github action for bulk of github test

[rfay]

The Issue

We now have the lovely github-action-add-on-test from @julienloizelet - THANKS!

This uses it.

[rfay]

Please confirm correctness @julienloizelet @tyler36

I also implemented this in ddev-platformsh

[julienloizelet]

Thanks @rfay ,

• We could remove the defaults part :

  ddev-addon-template/.github/workflows/tests.yml

  Lines 28 to 30 in f1d038d

  	defaults:
  	run:
  	shell: bash

We already set bash as shell in every step of the action because it is required to define one : https://github.com/ddev/github-action-add-on-test/blob/main/action.yaml#L63 for example

• We could remove the env part

  ddev-addon-template/.github/workflows/tests.yml

  Lines 22 to 24 in f1d038d

  	env:
  	# Allow ddev get to use a github token to prevent rate limiting by tests
  	DDEV_GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}

The DDEV_GITHUB_TOKEN value is already set in the action: https://github.com/ddev/github-action-add-on-test/blob/main/action.yaml#L98-L100

There's no harm in keeping it, but :

• the fewer things there are outside the action, the less maintenance is required
• If someone set the DDEV_GITHUB_TOKEN value outside the action, it will be overridden in the action by the token input value.
• Everyday, this run https://github.com/ddev/github-action-add-on-test/actions/workflows/add-ons-test.yml launches about 20 quasi simultaneous ddev get without reaching the API rate limit (It doesn't prove anything, but it suggests that it works.).

[tyler36]

Suggested change

11. Update the README.md to describe the add-on, how to use it, and how to contribute. If there are any manual actions that have to be taken, please explain them. If it requires special configuration of the using project, please explain how to do those. Examples in [ddev/ddev-solr](https://github.com/ddev/ddev-solr), [ddev/ddev-memcached](github.com/ddev/ddev-memcached), and (advanced) [ddev-platformsh](https://github.com/ddev/ddev-platformsh).

11. Update the README.md to describe the add-on, how to use it, and how to contribute. If there are any manual actions that have to be taken, please explain them. If it requires special configuration of the using project, please explain how to do those. Examples in [ddev/ddev-solr](https://github.com/ddev/ddev-solr), [ddev/ddev-memcached](github.com/ddev/ddev-memcached), and [ddev-platformsh](https://github.com/ddev/ddev-platformsh).

Not sure if you want to include advance or it is left over

[rfay]

It was intentional, it's a hard one to understand, but demonstrates the most exotic things I know to do with an add-on. Probably too exotic.

[tyler36]

It was intentional

Thank you for clarifying. Looks good to me.

[rfay]

See what you think now @julienloizelet - thanks for paying careful attention.