fix ipywidgets formatting issue

appendix-D/01_main-chapter-code/appendix-D.ipynb

@@ -165,14 +165,6 @@
      "text": [
       "135\n"
      ]
-    },
-    {
-     "name": "stderr",
-     "output_type": "stream",
-     "text": [
-      "/Users/sebastian/miniforge3/envs/book/lib/python3.11/site-packages/tqdm/auto.py:21: TqdmWarning: IProgress not found. Please update jupyter and ipywidgets. See https://ipywidgets.readthedocs.io/en/stable/user_install.html\n",
-      "  from .autonotebook import tqdm as notebook_tqdm\n"
-     ]
     }
    ],
    "source": [