Test submodule in github action #19659

Description:

Test submodule in github action

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

@peterhashair Thanks for this. But looking at the output it seems the action is first running a checkout including the submodules and afterwards a switch to the commit the tests should run for. So far that's fine, but I guess you would also need to do a submodule update afterwards, as otherwise the changes for the submodules won't be used. Or did I miss that?

@sgiehl add git submodule update --init --recursive