Replace all deprecated calls to entity.manager getStorage

...curring_events_registration/src/RegistrantListBuilder.php

src/EventInstanceListBuilder.php

src/EventSeriesListBuilder.php

src/Form/EventInstanceRevisionDeleteForm.php

src/Form/EventInstanceRevisionRevertForm.php

src/Form/EventInstanceRevisionRevertTranslationForm.php

src/Form/EventSeriesRevisionDeleteForm.php

src/Form/EventSeriesRevisionRevertForm.php

src/Form/EventSeriesRevisionRevertTranslationForm.php