fix: #3614865 Use getStorage() instead of a class property in WebformEntityListBuilder

Ben Stallingsrequested to merge
issue/webform-3614865:3614865-use-getstorage-instead into 6.3.x

Removed the unused submissionStorage, userStorage, and roleStorage class properties, which triggered a phpstan-drupal deprecation warning for caching entity storage instead of calling getStorage() at the call site.

Co-Authored-By: Claude Sonnet 5 noreply@anthropic.com

Closes #3614865

Merge request reports