Bump helmet from 3.21.1 to 3.21.2

Bumps [helmet](https://github.com/helmetjs/helmet) from 3.21.1 to 3.21.2.
- [Release notes](https://github.com/helmetjs/helmet/releases)
- [Changelog](https://github.com/helmetjs/helmet/blob/master/CHANGELOG.md)
- [Commits](helmetjs/helmet@v3.21.1...v3.21.2)

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

Author: dependabot-preview[bot]

package-lock.json

@@ -35,7 +35,7 @@
     "errorhandler": "^1.5.1",
     "express": "^4.17.1",
     "glob": "^7.1.6",
-    "helmet": "^3.21.1",
+    "helmet": "^3.21.2",
     "http-status": "^1.3.2",
     "mandrill-api": "^1.0.45",
     "node-dependency-injection": "^2.4.2",