feat(client): make errlog parameter optional in stdio_client

Author: sesajad

src/mcp/client/stdio/__init__.py

@@ -103,7 +103,7 @@ class StdioServerParameters(BaseModel):
 
 
 @asynccontextmanager
-async def stdio_client(server: StdioServerParameters, errlog: TextIO = sys.stderr):
+async def stdio_client(server: StdioServerParameters, errlog: TextIO | None = None):
     """
     Client transport for stdio: this will connect to a server by spawning a
     process and communicating with it over stdin/stdout.