Bump idna from 3.6 to 3.7 in /requirements/docs

Bumps [idna](https://github.com/kjd/idna) from 3.6 to 3.7.
- [Release notes](https://github.com/kjd/idna/releases)
- [Changelog](https://github.com/kjd/idna/blob/master/HISTORY.rst)
- [Commits](kjd/idna@v3.6...v3.7)

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

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

requirements/docs/requirements.txt

@@ -4,7 +4,7 @@ certifi==2024.2.2 ; python_version >= "3.8"
 charset-normalizer==3.3.2 ; python_version >= "3.8"
 colorama==0.4.6 ; python_version >= "3.8" and sys_platform == "win32"
 docutils==0.20.1 ; python_version >= "3.8"
-idna==3.6 ; python_version >= "3.8"
+idna==3.7 ; python_version >= "3.8"
 imagesize==1.4.1 ; python_version >= "3.8"
 importlib-metadata==7.1.0 ; python_version < "3.10" and python_version >= "3.8"
 jinja2==3.1.3 ; python_version >= "3.8"