refactor Controller to RestController

Author: javieralvarezin2

src/main/java/es/in2/vcverifier/oid4vp/controller/LoginQrController.java

@@ -5,15 +5,12 @@
 import org.springframework.http.HttpStatus;
 import org.springframework.stereotype.Controller;
 import org.springframework.ui.Model;
-import org.springframework.web.bind.annotation.GetMapping;
-import org.springframework.web.bind.annotation.RequestMapping;
-import org.springframework.web.bind.annotation.RequestParam;
-import org.springframework.web.bind.annotation.ResponseStatus;
+import org.springframework.web.bind.annotation.*;
 
 import java.io.ByteArrayOutputStream;
 import java.util.Base64;
 
-@Controller
+@RestController
 public class LoginQrController {