chore(deps): update markdown requirement in /docs/_build

Updates the requirements on [markdown](https://github.com/Python-Markdown/markdown) to permit the latest version.
- [Release notes](https://github.com/Python-Markdown/markdown/releases)
- [Changelog](https://github.com/Python-Markdown/markdown/blob/master/docs/changelog.md)
- [Commits](https://github.com/Python-Markdown/markdown/compare/3.11.2...3.11.3)

---
updated-dependencies:
- dependency-name: markdown
  dependency-version: 3.11.3
  dependency-type: direct:production
...

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

docs/_build/requirements.txt

@@ -3,7 +3,7 @@ click==8.5.0
 ghp-import==2.1.0
 importlib-metadata==10.1.0
 Jinja2==3.1.6
-Markdown>=3.11.2,<3.12
+Markdown>=3.11.3,<3.12
 MarkupSafe==3.0.4
 mergedeep==1.3.4
 mkdocs==1.6.1