Bump idna from 3.11 to 3.16

Bumps [idna](https://github.com/kjd/idna) from 3.11 to 3.16.
- [Release notes](https://github.com/kjd/idna/releases)
- [Changelog](https://github.com/kjd/idna/blob/master/HISTORY.md)
- [Commits](kjd/idna@v3.11...v3.16)

---
updated-dependencies:
- dependency-name: idna
  dependency-version: '3.16'
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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

Author: dependabot[bot]

requirements.txt

@@ -5,7 +5,7 @@ certifi==2026.2.25
 charset-normalizer==3.4.7
 click==8.1.8
 Flask==3.1.3
-idna==3.11
+idna==3.16
 itsdangerous==2.2.0
 Jinja2==3.1.6
 MarkupSafe==3.0.2