Add autowired to messageservice

server/application-server/src/main/java/de/tum/in/www1/hephaestus/chat/message/MessageController.java

@@ -1,23 +1,21 @@
 package de.tum.in.www1.hephaestus.chat.message;
 
+import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.http.ResponseEntity;
 import org.springframework.web.bind.annotation.GetMapping;
 import org.springframework.web.bind.annotation.PathVariable;
 import org.springframework.web.bind.annotation.PostMapping;
 import org.springframework.web.bind.annotation.RequestBody;
 import org.springframework.web.bind.annotation.RequestMapping;
 import org.springframework.web.bind.annotation.RestController;
-
 import java.util.List;
 
 @RestController
 @RequestMapping("/messages")
 public class MessageController {
-    private final MessageService messageService;
 
-    public MessageController(MessageService messageService) {
-        this.messageService = messageService;
-    }
+    @Autowired
+    private MessageService messageService;
 
     @GetMapping("/{sessionId}")
     public ResponseEntity<List<MessageDTO>> getMessages(@PathVariable Long sessionId) {