Merge pull request #4392 from matrix-org/neilj/fix_user_type_typo

ALL_USER_TYPES should be a tuple

changelog.d/4392.bugfix

+Fix typo in ALL_USER_TYPES definition to ensure type is a tuple

synapse/api/constants.py

@@ -128,4 +128,4 @@ class UserTypes(object):
     'admin' and 'guest' users should also be UserTypes. Normal users are type None
     """
     SUPPORT = "support"
-    ALL_USER_TYPES = (SUPPORT)
+    ALL_USER_TYPES = (SUPPORT,)