Bump markdown from 3.3.4 to 3.4.1

Bumps [markdown](https://github.com/Python-Markdown/markdown) from 3.3.4 to 3.4.1.
- [Release notes](https://github.com/Python-Markdown/markdown/releases)
- [Commits](Python-Markdown/markdown@3.3.4...3.4.1)

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

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

requirements.txt

@@ -10,7 +10,7 @@ geoalchemy2==0.4.2
 geojson==2.5.0
 geomet==0.3.0
 kombu==5.2.4
-Markdown==3.3.4 # at next update, please remove replace_marker() function in toc extension 
+Markdown==3.4.1 # at next update, please remove replace_marker() function in toc extension 
 phpserialize==1.3.0 # phpserialize is only required during the migration
 psycopg2==2.9.4
 pyjwt==1.7.1