[Refactor] reset RayServegRPCContext metadata initialize list construct

Signed-off-by: Cheng-Yeh Chung <[email protected]>

python/ray/serve/grpc_util.py

@@ -18,11 +18,15 @@ def __init__(self, grpc_context: grpc._cython.cygrpc._ServicerContext):
         self._auth_context = grpc_context.auth_context()
         self._code = grpc_context.code()
         self._details = grpc_context.details()
-        self._invocation_metadata = list(grpc_context.invocation_metadata())
+        self._invocation_metadata = [  # noqa: C416
+            (key, value) for key, value in grpc_context.invocation_metadata()
+        ]
         self._peer = grpc_context.peer()
         self._peer_identities = grpc_context.peer_identities()
         self._peer_identity_key = grpc_context.peer_identity_key()
-        self._trailing_metadata = list(grpc_context.trailing_metadata())
+        self._trailing_metadata = [  # noqa: C416
+            (key, value) for key, value in grpc_context.trailing_metadata()
+        ]
         self._compression = None
 
     def auth_context(self) -> Dict[str, Any]: