Bump markdown from 3.5.2 to 3.6 in /.github (#190)

Bumps [markdown](https://github.com/Python-Markdown/markdown) from 3.5.2 to 3.6.
- [Release notes](https://github.com/Python-Markdown/markdown/releases)
- [Changelog](https://github.com/Python-Markdown/markdown/blob/master/docs/changelog.md)
- [Commits](Python-Markdown/markdown@3.5.2...3.6)

---
updated-dependencies:
- dependency-name: markdown
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <support@github.com>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>
Co-authored-by: berndgassmann <bernd.gassmann@intel.com>

Author: dependabot[bot]

.github/workflows/requirements.txt

@@ -1,5 +1,5 @@
 colcon-common-extensions==0.3.0
-Markdown==3.5.2
+Markdown==3.6
 markdown-include==0.8.1
 mdx_truly_sane_lists==1.3
 mkdocs==1.5.3