fix: add correct sort

Author: AzulGarza

nbs/timegpt.ipynb

@@ -2111,7 +2111,8 @@
     "]\n",
     "for hyp in hyps:\n",
     "    fcst_test = timegpt.forecast(df_train, h=12, **hyp)\n",
-    "    fcst_test.insert(2, 'y', df_test['y'].values).sort_values(['unique_id', 'ds']).reset_index(drop=True)\n",
+    "    fcst_test.insert(2, 'y', df_test['y'].values)\n",
+    "    fcst_test = fcst_test.sort_values(['unique_id', 'ds']).reset_index(drop=True)\n",
     "    fcst_cv = timegpt.cross_validation(df_, h=12, **hyp)\n",
     "    fcst_cv = fcst_cv.sort_values(['unique_id', 'ds']).reset_index(drop=True)\n",
     "    pd.testing.assert_frame_equal(\n",