TST: GH30999 TESTING PR do not merge or review
There are 3 tests that don't run on my dev machine even with tweaks. They should fail in the CI and I can get the messages from there. So for now this is just a PR designed to run (and fail) the CI pipelines.

- [ ] closes #xxxx
- [ ] tests added / passed
- [ ] passes `black pandas`
- [ ] passes `git diff upstream/master -u -- "*.py" | flake8 --diff`
- [ ] whatsnew entry

Well. The CI succeeded without errors. Did not work as I intended. When you run pytest, you should see a message to this effect:

> test_sql.py::TestXMySQL::test_execute_fail SKIPPED                       [100%]
Skipped: gh-13611: there is no support for MySQL if SQLAlchemy is not installed

which is curious because I know I have SQLAlchemy installed. So a quick search for "13611" in the test code reveals:

    @pytest.mark.skip(
        reason="gh-13611: there is no support for MySQL if SQLAlchemy is not installed"
    )
    class TestXMySQL(MySQLMixIn):

Looks like this entire class is skipped even when SQLAlchemy is installed (there is no check). Uncommenting that line these tests need `pymysql` installed to run; and even with it installed they all fail for me. @rhshadrach Yes they fail for me too. That's why I decided to try in the CI pipeline.

I don't know where to go from here. I guess the options are:
1. Leave as-is, and leave the directories tests/compat and tests/io excluded from the pylint rule to be added as part of #30999 
2. Delete these tests entirely, since they seem to not ever be running anyway
3. Spend a good chunk of time really figuring out what is going on here, and what is the intended behaviour, including probably having to correctly configure MySQL on my dev machine > That's why I decided to try in the CI pipeline.

Don't you need to remove the `pytest.mark.skip` to try it? > > That's why I decided to try in the CI pipeline.
> 
> Don't you need to remove the `pytest.mark.skip` to try it?

Oh right. Thanks. That was a bit dumb of me. Setting up the pytest fixture doesn't work in the CI, just like on my dev machine. It looks like #13611 is open to remove most of these tests. I don't know if we want to bring that higher in the priority - I don't feel it's something I am qualified to do.