The `@dataProvider` annotation should be a static function, check and make data provider in the extension, at least:
- `EventFactoryTest` with `provideEventData`
- `ArticleViewHeaderHandlerTest` with `provideArticle`
- `ListParticipantsHandlerTest` with `provideRunData` and `provideRunErrors`
- `DeleteEventCommandTest` with `provideRegistrationAndStore`
- `EditEventCommandTest` with `providePageWithRegistrationAlreadyEnabled, `provideEditUnsafeErrors` and `provideEventRegistrations`
- `EventRegistrationTest` with `provideInvalidTimestampFormat`, `provideEventsForUTCConversion` and `provideAmbiguousLocalTimes`
- `EventPageCacheUpdaterTest` with `provideRegistrations`
- `PageMoveAndDeleteHandlerTest` with `providePageDelete`
- `CampaignsPageFactoryTest` with `provideTitleStrings`
- `MWPermissionsLookupTest` with `provideUserHasRight`, `provideUserIsSitewideBlocked` and `provideUserIsRegistered`
- `PageURLResolverTest` with `providePageAndURL`
- `RegisterParticipantCommandTest` with `provideInvalidRegistrationsAndErrors`, `provideStoreAndModified` and `provideRegisterUnsafeErrors`
- `UnregisterParticipantCommandTest` with `provideStoreAndModified` and `provideUnregisterUnsafeErrors`
- `PermissionCheckerTest` with `provideCanEnableRegistrations`, `provideCanOrganizeEvents`, `provideCanEnableRegistration`, `provideGenericEditPermissions`, `provideCanDeleteRegistration` and `provideCanRegisterForEvents`
- `CancelEventRegistrationHandlerTest` with `provideRequestDataWithErrors` and `provideRequestDataSuccessful`
- `DeleteEventRegistrationHandlerTest` with `provideErrorData`
- `EnableEventRegistrationHandlerTest` with `provideExecuteDataForValidationTest`
- `ListEventsByOrganizerHandlerTest` with `provideExecuteDataForEventListingTest`
- `ListEventsByParticipantHandlerTest` with `provideExecuteDataForEventListingTest`
- `ListOrganizersHandlerTest` with `provideRunData`
- `Rest\RegisterForEventHandlerTest` with `provideRequestDataWithErrors` and `provideRequestDataSuccessful`
- `RemoveParticipantsFromEventHandlerTest` with `provideRequestDataWithErrors` and `provideRequestDataSuccessful`
- `Rest\SetOrganizersHandlerTest` with `provideCommandErrors`
- `UpdateEventRegistrationHandlerTest` with `provideExecuteDataForValidationTest`
- `EventTimeFormatterTest` with `provideDates` and `provideTimezones`
static and adjust the usages (More infos at T332865).