docs: fix grammar errors in yi.ipynb and zhipuai.ipynb (#31441)

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docs/docs/integrations/chat/yi.ipynb

@@ -29,7 +29,7 @@
         "\n",
         "### Credentials\n",
         "\n",
-        "Head to [01.AI](https://platform.01.ai) to sign up to 01.AI and generate an API key. Once you've done this set the `YI_API_KEY` environment variable:"
+        "Head to [01.AI](https://platform.01.ai) to sign up for 01.AI and generate an API key. Once you've done this set the `YI_API_KEY` environment variable:"
       ]
     },
     {
@@ -197,7 +197,7 @@
       "source": [
         "## API reference\n",
         "\n",
-        "For detailed documentation of all ChatYi features and configurations head to the API reference: https://python.langchain.com/api_reference/community/chat_models/langchain_community.chat_models.yi.ChatYi.html"
+        "For detailed documentation of all ChatYi features and configurations, head to the API reference: https://python.langchain.com/api_reference/community/chat_models/langchain_community.chat_models.yi.ChatYi.html"
       ]
     }
   ],

docs/docs/integrations/chat/zhipuai.ipynb

@@ -56,7 +56,7 @@
    "metadata": {},
    "source": [
     "### Setting Up Your API Key\n",
-    "Sign in to [ZHIPU AI](https://open.bigmodel.cn/login?redirect=%2Fusercenter%2Fapikeys) for the an API Key to access our models."
+    "Sign in to [ZHIPU AI](https://open.bigmodel.cn/login?redirect=%2Fusercenter%2Fapikeys) for an API Key to access our models."
    ]
   },
   {