BREAKING: update mautrix to 0.15.x

vendor/maunium.net/go/mautrix/sqlstatestore/v02-membership-enum.sql

@@ -0,0 +1,6 @@
+-- v2: Use enum for membership field on Postgres
+-- only: postgres
+
+CREATE TYPE membership AS ENUM ('join', 'leave', 'invite', 'ban', 'knock');
+UPDATE mx_user_profile SET membership='leave' WHERE LOWER(membership) NOT IN ('join', 'leave', 'invite', 'ban', 'knock');
+ALTER TABLE mx_user_profile ALTER COLUMN membership TYPE membership USING LOWER(membership)::membership;