[shim] Fix socket binding address

As there is no need in "-socket" flag, we'd better use SOCKET_FD as the binding address of task server only.

Signed-off-by: Burning <burning9699@gmail.com>

crates/shim/src/lib.rs

@@ -253,11 +253,7 @@ where
             let task_service = create_task(Arc::new(Box::new(task)));
             let mut server = Server::new().register_service(task_service);
 
-            server = if flags.socket.is_empty() {
+            server = server.add_listener(SOCKET_FD)?;
-                server.add_listener(SOCKET_FD)?
-            } else {
-                server.bind(&flags.socket)?
-            };
 
             server.start()?;