add common setting and lint

Part-of: <https://dev.funkwhale.audio/funkwhale/funkwhale/-/merge_requests/2607>

api/config/settings/common.py

@@ -1484,3 +1484,10 @@ Typesense hostname. Defaults to `localhost` on non-Docker deployments and to `ty
 Docker deployments.
 """
 TYPESENSE_NUM_TYPO = env("TYPESENSE_NUM_TYPO", default=5)
+
+ONLY_ALLOW_MUSICBRAINZ_TAGGED_FILES = env(
+    "ONLY_ALLOW_MUSICBRAINZ_TAGGED_FILES", default=False
+)
+"""
+If True, files without a Musicbrainz id will not be uploaded.
+"""

api/tests/music/test_tasks.py

@@ -1417,7 +1417,7 @@ def test_upload_checks_mbid_tag(temp_signal, factories, mocker):
     )
     mocker.patch("funkwhale_api.music.models.TrackActor.create_entries")
 
-    with temp_signal(signals.upload_import_status_updated) as handler:
+    with temp_signal(signals.upload_import_status_updated):
         tasks.process_upload(upload_id=upload.pk)
 
     upload.refresh_from_db()