Fix "call to undefined' PHPStan-0 issues in migration system

Seems straight forward and does address the phpstan issues. Wondered if we should add typehints but probably would be a stretch of scope.

Rebased, these was a conflict in the phpstan baseline.

Added some comments to the MR. I feel that we shouln't make breaking changes or have extra to maintain just because PHPStan can't work something out.

And in my work on this I also removed unnecessary usages of CreateTestContentEntitiesTrait.

The Needs Review Queue Bot → tested this issue. It no longer applies to Drupal core. Therefore, this issue status is now "Needs work".

This does not mean that the patch necessarily needs to be re-rolled or the MR rebased. Read the Issue Summary, the issue tags and the latest discussion here to determine what needs to be done.

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Rebase and regenerate the baseline.

Tried adding a return type to the new method but got

Return type mixed of method                                                           
         Drupal\Tests\migrate_drupal_ui\Functional\d7\FilePathTest::getManagedFiles()          
         is not covariant with return type array of method                                     
         Drupal\Tests\migrate_drupal_ui\Functional\MigrateUpgradeTestBase::getManagedFiles().  
 ------ -------------------------------------------------------------------------------------- 

Re-ran unit test failure and was random.

+1 from me but there are 2 open threads from @alexpott what are your thoughts on the responses?

Going to go out on a limb and mark this one. If premature I apologize.

Added one small docs thing to fix

binoli lalani → made their first commit to this issue’s fork.