6 files declare their use of ResourceBase in Drupal 8

DBLogResource.php in core/modules/dblog/src/Plugin/rest/resource/DBLogResource.php

EntityResource.php in core/modules/rest/src/Plugin/rest/resource/EntityResource.php

FileUploadResource.php in core/modules/file/src/Plugin/rest/resource/FileUploadResource.php

NoSerializationClassTestResource.php in core/modules/rest/tests/modules/rest_test/src/Plugin/rest/resource/NoSerializationClassTestResource.php

RequestHandlerTest.php in core/modules/rest/tests/src/Kernel/RequestHandlerTest.php

UserRegistrationResource.php in core/modules/user/src/Plugin/rest/resource/UserRegistrationResource.php