chore(deps): bump helmet from 4.4.1 to 5.0.2

Bumps [helmet](https://github.com/helmetjs/helmet) from 4.4.1 to 5.0.2.
- [Release notes](https://github.com/helmetjs/helmet/releases)
- [Changelog](https://github.com/helmetjs/helmet/blob/main/CHANGELOG.md)
- [Commits](https://github.com/helmetjs/helmet/compare/v4.4.1...v5.0.2)

---
updated-dependencies:
- dependency-name: helmet
  dependency-type: direct:production
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <support@github.com>

plugins/app-backend/package.json

@@ -42,7 +42,7 @@
     "express": "^4.17.1",
     "express-promise-router": "^4.1.0",
     "fs-extra": "9.1.0",
-    "helmet": "^4.0.0",
+    "helmet": "^5.0.2",
     "knex": "^1.0.2",
     "lodash": "^4.17.21",
     "luxon": "^2.0.2",