TASK: Use correct @template-covariant tag for ProjectionFactoryInterface

[mhsdesign]

See also 329330e

See https://phpstan.org/blog/whats-up-with-template-covariant

Solves that

$projectionsFactory = new ProjectionsAndCatchUpHooksFactory();
$projectionsFactory->registerFactory(new DoctrineDbalContentGraphProjectionFactory($this->dbalClient), []);

yields when being used stand alone:

  172    Parameter #1 $factory of method Neos\ContentRepository\Core\Factory\ProjectionsAndCatchUpHooksFactory::registerFactory() expects                                                                                                                                                            
         Neos\ContentRepository\Core\Projection\ProjectionFactoryInterface<Neos\ContentRepository\Core\Projection\ProjectionInterface<Neos\ContentRepository\Core\Projection\ProjectionStateInterface>>, Neos\ContentGraph\DoctrineDbalAdapter\DoctrineDbalContentGraphProjectionFactory given.      
         💡 Template type T on class Neos\ContentRepository\Core\Projection\ProjectionFactoryInterface is not covariant. Learn more: https://phpstan.org/blog/whats-up-with-template-covariant                                                                                                       
         ✏️  file:///Users/marchenryschultz/Code/lab/standalone-content-repository/src/StandaloneContentRepositoryRegistry.php:172  

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