Fix StaticUserManager hashability and all_groups

auth.py

@@ -95,7 +95,7 @@ class StaticUserManager:
             for (username, password, groups) in users
         }
         self.group_map = {
-            username: groups
+            username: tuple(groups)
             for (username, password, groups) in users
         }
         self.obsolete = obsolete
@@ -109,7 +109,10 @@ class StaticUserManager:
             yield from self.group_map[username]
 
     def all_groups(self, username, password):
-        yield from list(set(group for group in self.group_map.values()))
+        yield from list(set(
+            group
+            for groups in self.group_map.values()
+            for group in groups))
 
 
 try: