The `TopicCreator` class has a `skip_validations` option that can force-create a topic without performing permission checks or validation rules. However, at the moment it doesn't skip validations that are related to tags, so topics that are created by the system or by some scrip can still fail if they use tags. This commit makes the `TopicCreator` class skip all tags-related checks if the `skip_validations` is specified.
Internal topic: t/124280.
72c4709a5a