fix: upgrade @testing-library/jest-dom from 6.5.0 to 6.6.2

Snyk has created this PR to upgrade @testing-library/jest-dom from 6.5.0 to 6.6.2.

See this package in npm:
@testing-library/jest-dom

See this project in Snyk:
https://app.snyk.io/org/tsmoreland/project/1c13af47-6938-4c00-ab6d-8ec15f8c2739?utm_source=github&utm_medium=referral&page=upgrade-pr

Author: snyk-bot

frontend/package-lock.json

@@ -3,7 +3,7 @@
   "version": "0.1.0",
   "private": true,
   "dependencies": {
-    "@testing-library/jest-dom": "^6.5.0",
+    "@testing-library/jest-dom": "^6.6.2",
     "@testing-library/react": "^13.4.0",
     "@testing-library/user-event": "^13.5.0",
     "react": "^18.3.1",