do not crash when authentication with server fails. Fixes #8115

src/common/connection.py

@@ -1512,7 +1512,7 @@ def __on_auth(self, con, auth):
             if self.on_connect_auth:
                 self.on_connect_auth(None)
                 self.on_connect_auth = None
-                return
+            return
         if not self.connected: # We went offline during connecting process
             if self.on_connect_auth:
                 self.on_connect_auth(None)