Update dependency express to v5

Signed-off-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>

Author: renovate[bot]

plugins/notifications-tester-backend/package.json

@@ -26,12 +26,12 @@
     "@backstage/backend-plugin-api": "backstage:^",
     "@backstage/config": "backstage:^",
     "@backstage/plugin-notifications-node": "backstage:^",
-    "express": "^4.17.1",
+    "express": "^5.0.0",
     "express-promise-router": "^4.1.0"
   },
   "devDependencies": {
     "@backstage/cli": "backstage:^",
-    "@types/express": "^4.17.6"
+    "@types/express": "^5.0.0"
   },
   "files": [
     "dist",