Allow to distinguish between MySQL and MariaDB (also in installation)

[sgiehl]

Description:

This is a small draft how to solve issues that might occur in MariaDb only.
I've only spent a couple of minutes to do the changes, so I'm not even sure if it would even fully work.

I currently don't have time to finish this PR or even test if everything works as expected.
If someone has some time, feel free to pick it up.

When finished this aims to fix #18360

This PR will change some test runs to use MariaDb instead of MySQL. This currently only affects PHP tests (Unit, Integration, System). Due to some fixtures using the same datetime for their visits, the UI tests would currently fail on MariaDb due to different sorting behaviour compared to MySQL.

Requires matomo-org/github-action-tests#16 and matomo-org/plugin-MarketingCampaignsReporting#152

Review

• Functional review done
• Potential edge cases thought about (behavior of the code with strange input, with strange internal state or possible interactions with other Matomo subsystems)
• Usability review done (is anything maybe unclear or think about anything that would cause people to reach out to support)
• Security review done
• Wording review done
• Code review done
• Tests were added if useful/possible
• Reviewed for breaking changes
• Developer changelog updated if needed
• Documentation added if needed
• Existing documentation updated if needed

[jorgeuos]

I'm curios though if there's other functionality that looks for SELECT in their queries. And if it would break backwards compatibility. Haven't had time to look into that yet.
Considering the comment from @tsteur here: #18360 (comment)
Mostly just core DB updates I would guess, but IDK right now.
Although don't think it's related to why the build failed: https://app.travis-ci.com/github/matomo-org/matomo/jobs/549521319#L1078
I would need to run the tests locally first.

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