build(deps): bump nodemailer in /apps/OpenSignServer

Bumps [nodemailer](https://github.com/nodemailer/nodemailer) from 6.9.15 to 6.9.16.
- [Release notes](https://github.com/nodemailer/nodemailer/releases)
- [Changelog](https://github.com/nodemailer/nodemailer/blob/master/CHANGELOG.md)
- [Commits](nodemailer/nodemailer@v6.9.15...v6.9.16)

---
updated-dependencies:
- dependency-name: nodemailer
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

Signed-off-by: dependabot[bot] <[email protected]>

Author: dependabot[bot]

apps/OpenSignServer/package-lock.json

@@ -39,7 +39,7 @@
     "multer": "^1.4.5-lts.1",
     "multer-s3": "^3.0.1",
     "node-forge": "^1.3.1",
-    "nodemailer": "^6.9.15",
+    "nodemailer": "^6.9.16",
     "parse": "^5.3.0",
     "parse-dbtool": "^1.2.0",
     "parse-server": "^7.3.0",