Cancel the job if the signature is still invalid after a refetch of the public key

lib/pleroma/workers/receiver_worker.ex

@@ -50,7 +50,7 @@ defp process_errors(errors) do
       {:error, {:validate_object, reason}} -> {:cancel, reason}
       {:error, {:error, {:validate, reason}}} -> {:cancel, reason}
       {:error, {:reject, reason}} -> {:cancel, reason}
-      {:signature, false} -> {:error, :invalid_signature}
+      {:signature, false} -> {:cancel, :invalid_signature}
       {:error, {:error, reason = "Object has been deleted"}} -> {:cancel, reason}
       e -> e
     end