Bump pynacl from 1.6.1 to 1.6.2 in /docs/sphinx (#5836)

Bumps [pynacl](https://github.com/pyca/pynacl) from 1.6.1 to 1.6.2.
- [Changelog](https://github.com/pyca/pynacl/blob/main/CHANGELOG.rst)
- [Commits](https://github.com/pyca/pynacl/compare/1.6.1...1.6.2)

---
updated-dependencies:
- dependency-name: pynacl
  dependency-version: 1.6.2
  dependency-type: indirect
...

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Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

docs/sphinx/requirements.txt

@@ -164,7 +164,7 @@ pygments==2.19.2
     #   sphinx
 pyjwt[crypto]==2.10.1
     # via pygithub
-pynacl==1.6.1
+pynacl==1.6.2
     # via pygithub
 python-dateutil==2.9.0.post0
     # via jupyter-client