fix typo in qaoa cn

Author: refraction-ray

docs/source/tutorials/qaoa_cn.ipynb

@@ -175,9 +175,7 @@
    "cell_type": "code",
    "execution_count": 5,
    "source": [
-    "params = K.implicit_randn(\n",
-    "    shape=[ncircuits, 2 * nlayers], stddev=0.1\n",
-    ")  # 初始参数\n",
+    "params = K.implicit_randn(shape=[ncircuits, 2 * nlayers], stddev=0.1)  # 初始参数\n",
     "opt = K.optimizer(tf.keras.optimizers.Adam(1e-2))\n",
     "\n",
     "for i in range(50):\n",