Merge pull request #5389 from matrix-org/erikj/renew_attestations_on_master

Only start background group attestation renewals on master

changelog.d/5389.bugfix

@@ -0,0 +1 @@
+Fix exceptions in federation reader worker caused by attempting to renew attestations, which should only happen on master worker.

synapse/groups/attestations.py

@@ -132,6 +132,7 @@ class GroupAttestionRenewer(object):
         self.is_mine_id = hs.is_mine_id
         self.attestations = hs.get_groups_attestation_signing()
 
+        if not hs.config.worker_app:
             self._renew_attestations_loop = self.clock.looping_call(
                 self._start_renew_attestations, 30 * 60 * 1000,
             )