Don't crash on menuItems without keys

Author: manisandro

src/qwc2_viewer.py

@@ -533,7 +533,7 @@ def __replace_login__helper_items(self, items, signed_in, hide):
         """
         removeIndex = None
         for (idx, item) in enumerate(items):
-            if item["key"] == "Login" and signed_in:
+            if item.get("key") == "Login" and signed_in:
                 if hide:
                     removeIndex = idx
                     break