fix: upgrade next from 14.2.26 to 14.2.28

Snyk has created this PR to upgrade next from 14.2.26 to 14.2.28.

See this package in npm:
next

See this project in Snyk:
https://app.snyk.io/org/sswietoniowski/project/c4fde6b3-13e3-462b-b325-9990f3ceb289?utm_source=github&utm_medium=referral&page=upgrade-pr

Author: snyk-bot

projects/react/08_conference_speakers/package-lock.json

@@ -13,7 +13,7 @@
   "license": "ISC",
   "dependencies": {
     "axios": "^1.8.4",
-    "next": "^14.2.26",
+    "next": "^14.2.28",
     "react": "^18.3.1",
     "react-bootstrap": "^2.10.9",
     "react-dom": "^18.3.1"