chore(deps): bump markdown from 3.8.2 to 3.9

Bumps [markdown](https://github.com/Python-Markdown/markdown) from 3.8.2 to 3.9.
- [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@3.8.2...3.9.0)

---
updated-dependencies:
- dependency-name: markdown
  dependency-version: '3.9'
  dependency-type: indirect
  update-type: version-update:semver-minor
...

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

Author: dependabot[bot]

requirements/docs-blog.txt

@@ -240,9 +240,9 @@ jinja2==3.1.6 \
     # via
     #   mkdocs
     #   mkdocs-material
-markdown==3.8.2 \
-    --hash=sha256:247b9a70dd12e27f67431ce62523e675b866d254f900c4fe75ce3dda62237c45 \
-    --hash=sha256:5c83764dbd4e00bdd94d85a19b8d55ccca20fe35b2e678a1422b380324dd5f24
+markdown==3.9 \
+    --hash=sha256:9f4d91ed810864ea88a6f32c07ba8bee1346c0cc1f6b1f9f6c822f2a9667d280 \
+    --hash=sha256:d2900fe1782bd33bdbbd56859defef70c2e78fc46668f8eb9df3128138f2cb6a
     # via
     #   mkdocs
     #   mkdocs-material

requirements/docs-user.txt

@@ -146,9 +146,9 @@ jinja2==3.1.6 \
     #   mkdocs
     #   mkdocs-macros-plugin
     #   mkdocs-material
-markdown==3.8.2 \
-    --hash=sha256:247b9a70dd12e27f67431ce62523e675b866d254f900c4fe75ce3dda62237c45 \
-    --hash=sha256:5c83764dbd4e00bdd94d85a19b8d55ccca20fe35b2e678a1422b380324dd5f24
+markdown==3.9 \
+    --hash=sha256:9f4d91ed810864ea88a6f32c07ba8bee1346c0cc1f6b1f9f6c822f2a9667d280 \
+    --hash=sha256:d2900fe1782bd33bdbbd56859defef70c2e78fc46668f8eb9df3128138f2cb6a
     # via
     #   mkdocs
     #   mkdocs-material