build(deps): bump nodemailer from 7.0.7 to 7.0.11 in /backend

Bumps [nodemailer](https://github.com/nodemailer/nodemailer) from 7.0.7 to 7.0.11.
- [Release notes](https://github.com/nodemailer/nodemailer/releases)
- [Changelog](https://github.com/nodemailer/nodemailer/blob/master/CHANGELOG.md)
- [Commits](nodemailer/nodemailer@v7.0.7...v7.0.11)

---
updated-dependencies:
- dependency-name: nodemailer
  dependency-version: 7.0.11
  dependency-type: direct:production
...

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

Author: dependabot[bot]

backend/package.json

@@ -49,7 +49,7 @@
     "mjml": "4.15.0",
     "mongodb": "6.3.0",
     "mustache": "4.2.0",
-    "nodemailer": "7.0.7",
+    "nodemailer": "7.0.11",
     "object-hash": "3.0.0",
     "prom-client": "15.1.3",
     "rate-limiter-flexible": "5.0.3",