Remove outdated cell output.

Author: Chahan Kropf

doc/user-guide/climada_entity_MeasureSet.ipynb

@@ -560,25 +560,14 @@
   },
   {
    "cell_type": "code",
-   "execution_count": 7,
+   "execution_count": null,
    "metadata": {
     "ExecuteTime": {
      "end_time": "2021-03-05T12:22:41.336852Z",
      "start_time": "2021-03-05T12:22:41.266438Z"
     }
    },
-   "outputs": [
-    {
-     "data": {
-      "text/plain": [
-       "<climada.entity.measures.measure_set.MeasureSet at 0x1f30d913b80>"
-      ]
-     },
-     "execution_count": 1,
-     "metadata": {},
-     "output_type": "execute_result"
-    }
-   ],
+   "outputs": [],
    "source": [
     "from climada.entity.measures import MeasureSet\n",
     "from climada.util import ENT_TEMPLATE_XLS\n",