[Notebook] Fix bug

Author: matteobettini

notebooks/Simulation_and_training_in_VMAS_and_BenchMARL.ipynb

@@ -2160,8 +2160,10 @@
     "    device: DEVICE_TYPING,\n",
     ") -> Callable[[], EnvBase]:\n",
     "    config = copy.deepcopy(self.config)\n",
-    "    if self is VmasTask.NAVIGATION: # This is the only modification we make ....\n",
-    "        scenario = MyScenario() # .... ends here\n",
+    "    if (hasattr(self, \"name\") and self.name is \"NAVIGATION\") or (\n",
+    "        self is VmasTask.NAVIGATION\n",
+    "    ):  # This is the only modification we make ....\n",
+    "        scenario = MyScenario()  # .... ends here\n",
     "    else:\n",
     "        scenario = self.name.lower()\n",
     "    return lambda: VmasEnv(\n",