update task functionality

frontend/allowance-planner-v2/src/app/services/task.service.ts

@@ -22,4 +22,8 @@ export class TaskService {
     createTask(task: Partial<Task>) {
         this.http.post(`${this.url}/tasks`, task).subscribe();
     }
+
+    updateTask(id: number, task: Partial<Task>) {
+        this.http.put(`${this.url}/task/${id}`, task).subscribe();
+    }
 }