Fixed broken frontend test

Dockerfile

@@ -35,4 +35,4 @@ EXPOSE 80 8000
 COPY start.sh /start.sh
 RUN chmod +x /start.sh
 
-CMD ["/start.sh"] 
+CMD ["/start.sh"]

frontend/src/tests/App.test.tsx

@@ -1,5 +1,6 @@
 import { render, screen } from '@testing-library/react';
 import userEvent from '@testing-library/user-event';
+import '@testing-library/jest-dom';
 import App from '../App';
 
 describe('App', () => {

frontend/tsconfig.json

@@ -15,7 +15,12 @@
     "isolatedModules": true,
     "noEmit": true,
     "jsx": "react-jsx",
-    "types": ["jest", "node"]
+    "types": [
+      "jest", 
+      "node", 
+      "@testing-library/jest-dom",
+      "@testing-library/user-event"
+    ]
   },
   "include": ["src/**/*"],
   "exclude": ["node_modules"]