json(..) 수정

src/main/java/cokr/xit/foundation/web/WebClient.java

@@ -376,7 +376,8 @@ public class WebClient {
 		 */
 		public Request json(JSON json) {
 			this.json = json;
-			return contentType(ContentType.JSON);
+			contentType(ContentType.JSON);
+			return header("Accept", ContentType.JSON.type);
 		}
 
 		private JSON json() {