Run tests for mysql 5.x without a github ubuntu-18.04 image

[atercattus]

ubuntu-18.04 image is deprecated already. We use this image for mysql 5.7 image.

We should use another way to run old MySQL versions.

[lance6716]

closed by 779

[atercattus]

Unfortunately, this it not be done with #779, because 20.04 and 22.04 images use only mysql8.0.32: 20.04 and 22.04.

[dveeden]

I think we now use:

• Ubuntu 22.04, Ubutu 24.04 and "ubuntu-latest" in CI. These should all be supported.
• We test with MySQL 8.0.x and 8.4.x. These are the LTS versions that are in support.
• We don't test with MySQL 5.7.x (which is EOL). I would like to test with 5.7 if possible.

Suggestions:

• Run with a MySQL service like this: https://github.com/perl5-dbi/DBD-mysql/blob/f9eab6a80d973c80b20920a15b46238fd2a1eebf/.github/workflows/ci.yml#L32-L41
• With either the container registry from Oracle or Docker.

[dveeden]

We could probably use a modified image with TLS and binlogs enabled.
I created this: https://github.com/dveeden/mysql57test

However publishing this on ghcr or docker hub seems quite complicated.