Only set requests in tracking request set when correct value is given #17877

refs https://github.com/matomo-org/plugin-QueuedTracking/issues/153#issuecomment-896856651

fix https://github.com/matomo-org/plugin-QueuedTracking/issues/153

Possible warning:

/usr/share/piwik/core/Tracker/RequestSet.php(36): Warning - Invalid argument supplied for foreach() -

Not sure how this would happen and it might hide an actual error maybe. I've been looking through code for a while and couldn't really see where this might happen. The only one I could find was bulk tracking a wrong JSON being set. Maybe we should throw an invalid tracking parameter exception when requests is not an array? https://github.com/matomo-org/matomo/blob/4.4.1/plugins/BulkTracking/Tracker/Requests.php#L78

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 see checklist
• [ ] 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

User confirmed it works so far.