fix: get paddle_col from last row

Author: kibitzing

examples/OpenEnv_Tutorial.ipynb

@@ -1021,8 +1021,10 @@
     "        for idx, val in enumerate(info_state):\n",
     "            if abs(val - 1.0) < 0.01:  # Ball\n",
     "                ball_col = idx % grid_size\n",
-    "            elif abs(val - 0.5) < 0.01:  # Paddle\n",
-    "                paddle_col = idx % grid_size\n",
+    "                break\n",
+    "\n",
+    "        last_row = info_state[-grid_size:]\n",
+    "        paddle_col = last_row.index(1.0)\n",
     "\n",
     "        if ball_col is not None and paddle_col is not None:\n",
     "            if paddle_col < ball_col:\n",