[PHP 8.4] Explicitly mark nullable parameters

[sgiehl]

Description:

With PHP 8.4 implicitly marking parameters as nullable by only setting null as default value is deprecated. To get rid of all the deprecation notices caused by our code, this PR aims to change all occurrences to explicitly mark the parameters as nullable.

refs #22471

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

[michalkleiner]

Did you use a tool to convert the params or did you do it manually?

[sgiehl]

@michalkleiner I actually used a regex to find those and fixed them manually. Might be possible that I missed some though. But I didn't want to introduce new type hints on purpose and only fixed those that had an implicit nullable value.

[michalkleiner]

implicit nullable value.

Implicit nullable typed value. Fair enough.