Minor fix for newest stable clippy

Signed-off-by: Bob Weinand <bob.weinand@datadoghq.com>

remote-config/src/fetch/test_server.rs

@@ -54,7 +54,7 @@ impl RemoteConfigServer {
                         async move {
                             let body_bytes = hyper::body::to_bytes(req.into_body()).await.unwrap();
                             let request: ClientGetConfigsRequest = serde_json::from_str(
-                                &String::from_utf8(body_bytes.to_vec()).unwrap(),
+                                core::str::from_utf8(&body_bytes).unwrap(),
                             )
                             .unwrap();
                             let response =