[Chore] 포트변경 2

Author: neibler

src/main/java/com/ongil/backend/PingController.java

@@ -8,6 +8,6 @@ public class PingController {
 
     @GetMapping("/ping")
     public String ping() {
-        return "pong2";
+        return "pong";
     }
 }