cli: ensure the connection always get closed in github.py (#31914)

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libs/cli/langchain_cli/utils/github.py

@@ -3,26 +3,30 @@ import json
 from typing import Optional
 
 
-def list_packages(*, contains: Optional[str] = None):
+def list_packages(*, contains: Optional[str] = None) -> list[str]:
     conn = http.client.HTTPSConnection("api.github.com")
+    try:
+        headers = {
+            "Accept": "application/vnd.github+json",
+            "X-GitHub-Api-Version": "2022-11-28",
+            "User-Agent": "langchain-cli",
+        }
 
-    headers = {
-        "Accept": "application/vnd.github+json",
-        "X-GitHub-Api-Version": "2022-11-28",
-        "User-Agent": "langchain-cli",
-    }
+        conn.request(
+            "GET",
+            "/repos/langchain-ai/langchain/contents/templates",
+            headers=headers,
+        )
+        res = conn.getresponse()
 
-    conn.request(
-        "GET",
-        "/repos/langchain-ai/langchain/contents/templates",
-        headers=headers,
-    )
-    res = conn.getresponse()
+        res_str = res.read()
 
-    res_str = res.read()
-
-    data = json.loads(res_str)
-    package_names = [
-        p["name"] for p in data if p["type"] == "dir" and p["name"] != "docs"
-    ]
-    return [p for p in package_names if contains in p] if contains else package_names
+        data = json.loads(res_str)
+        package_names = [
+            p["name"] for p in data if p["type"] == "dir" and p["name"] != "docs"
+        ]
+        return (
+            [p for p in package_names if contains in p] if contains else package_names
+        )
+    finally:
+        conn.close()