Update coding standards in recurring_events core module

config/install/recurring_events.eventseries_type.default.yml

recurring_events.api.php

recurring_events.info.yml

recurring_events.install

recurring_events.libraries.yml

recurring_events.module

recurring_events.permissions.yml

recurring_events.routing.yml

recurring_events.services.yml

src/Entity/EventInstance.php

src/Entity/EventSeries.php

src/EventCreationService.php

src/EventInstanceTypeHtmlRouteProvider.php

src/EventInterface.php

src/EventSeriesTypeHtmlRouteProvider.php

src/ExcludedDatesHtmlRouteProvider.php

src/Form/EventInstanceForm.php

src/Form/EventInstanceRevisionDeleteForm.php

src/Form/EventInstanceRevisionRevertForm.php

src/Form/EventInstanceRevisionRevertTranslationForm.php