Move Phabricator import workers to correct location

These should be in app/workers. If they aren't, they won't be picked up
by every_sidekiq_worker_spec.rb, and their queues won't be guaranteed to
be in all_queues.yml, which in turn prevents sidekiq-cluster from seeing
them.

Making the BaseWorker not include ApplicationWorker means that we don't
need to act as if it has its own queue. (See HashedStorage::BaseWorker,
which does the same thing.)

app/workers/all_queues.yml

@@ -192,3 +192,4 @@
 - self_monitoring_project_create
 - self_monitoring_project_delete
 - merge_request_mergeability_check
+- phabricator_import_import_tasks

lib/gitlab/phabricator_import/base_worker.rb → app/workers/gitlab/phabricator_import/base_worker.rb

@@ -19,8 +19,7 @@
 module Gitlab
   module PhabricatorImport
     class BaseWorker
-      include ApplicationWorker
-      include ProjectImportOptions # This marks the project as failed after too many tries
+      include WorkerAttributes
       include Gitlab::ExclusiveLeaseHelpers
 
       feature_category :importers

lib/gitlab/phabricator_import/import_tasks_worker.rb → app/workers/gitlab/phabricator_import/import_tasks_worker.rb

@@ -2,6 +2,9 @@
 module Gitlab
   module PhabricatorImport
     class ImportTasksWorker < BaseWorker
+      include ApplicationWorker
+      include ProjectImportOptions # This marks the project as failed after too many tries
+
       def importer_class
         Gitlab::PhabricatorImport::Issues::Importer
       end