Revert

Author: stevebauman

src/Models/Model.php

@@ -617,7 +617,7 @@ protected function determineMorphModel(Model $model, array $models, callable $re
             );
         }
 
-        $objectClasses = static::$morphCache[static::class] ??= $this->normalizeObjectClasses(
+        $objectClasses = $this->normalizeObjectClasses(
             $model->getObjectClasses()
         );