Add MySQL example.

[Potherca]

I thought it might be useful to have a working example for MySQL, in case folks want/need to use a different version from the installed default.

I've tried to make the code look similar to already existing examples.

The example can be seen working here: https://github.com/potherca-contrib/example-services/actions/runs/449593636

If you have any feedback, please let me know! 👍

[jrfnl]

While trying to get the VM version working, in my specific case, I still did not succeed unless I made the following additional changes.

Also see: https://github.community/t/how-to-use-a-different-mysql-version-than-the-default-5-7-in-a-gh-action/152403/

[jrfnl]

Suggested change

	- 3306/tcp
	- 3306:3306

[jrfnl]

Suggested change

	MYSQL_PORT: ${{ job.services.mysql.ports[3306] }} # get randomly assigned published port
	MYSQL_PORT: 3306

[Potherca]

@jrfnl I'd be curious to know why job.services.<service id>.ports did not work... but other than that, I am very much inclined to include your edit. 👍

Maybe @andymckay or @chrispat could comment on this?

[jrfnl]

@Potherca I honestly wouldn't know. I also found that using 127.0.0.1 (or in practice: 127.0.0.1:3306) worked better than using localhost. But to be honest, I tried so much that it is hard to say which bit was the bit which fixed it.

In the end, the changes I needed for this particular workflow were quite small, but the complete combi was needed to get it all working. Relevant commits:

• WordPress/wordpress-importer@122fdc2
• WordPress/wordpress-importer@5bc6b88