Migrate the remaining k8s workers to default

After #1074 (closed), we can do the same for other workers.

Migration steps

Same as in #1074 (closed).

1. Update the last rule in the routing configuration to be: ["*", "default"] (instead of routing to null/nil . We can also delete any feature-category-specific routes to default added in #1074 (closed)
2. Validate that the jobs are processed through the default queue using logs and metrics.
3. Migrate any scheduled and to-be-retried jobs using the Rake task from gitlab-org/gitlab!60724 (merged)
4. Change catchall-on-k8s to only listen to default, mailers, and project_import_schedule
   • In the k8sworkloads configuration for catchall, set queueSelector: false, and 'queues: default,mailers,project_import_schedule,service_desk_email_receiver'