fix closing of http.Response and http.Request bodies

http3/client.go

@@ -187,7 +187,7 @@ func (c *client) RoundTrip(req *http.Request) (*http.Response, error) {
 			res.Header.Add(hf.Name, hf.Value)
 		}
 	}
-	respBody := newResponseBody(&responseBody{str})
+	respBody := newResponseBody(str)
 	if requestGzip && res.Header.Get("Content-Encoding") == "gzip" {
 		res.Header.Del("Content-Encoding")
 		res.Header.Del("Content-Length")