Bump nodemailer from 6.7.7 to 6.9.9

Bumps [nodemailer](https://github.com/nodemailer/nodemailer) from 6.7.7 to 6.9.9.
- [Release notes](https://github.com/nodemailer/nodemailer/releases)
- [Changelog](https://github.com/nodemailer/nodemailer/blob/master/CHANGELOG.md)
- [Commits](nodemailer/nodemailer@v6.7.7...v6.9.9)

---
updated-dependencies:
- dependency-name: nodemailer
  dependency-type: direct:production
...

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

package.json

@@ -62,7 +62,7 @@
     "js-yaml": "^3.14.1",
     "jsonwebtoken": "^8.5.1",
     "mailgun-js": "^0.22.0",
-    "nodemailer": "^6.7.7",
+    "nodemailer": "^6.9.9",
     "pdfjs": "^2.4.7",
     "pg": "^8.6.0",
     "reflect-metadata": "^0.1.13",