PHPStan fixes + other minor adjustments

Should add a gitlab file so these get caught early.

Hi @ smustgrave

Thx for your input but this issue does not cover adding extra things like the Gitlab file. I assume, there needs to be another issue for that purpose.

p.s Besides, this particular issue has an assigned person and it is in review, please, do not update the status when it's not yet reviewed.

Regards,
Andrei

Adding a gitlab file is the suggestion we've been making for those credit farming phpcs fixes. But I don't pay much attention to this module so don't have much stack in if we add it.

nick.murza → made their first commit to this issue’s fork.

it's good. Great job. Merged.