Bump markdown2 from 2.4.2 to 2.4.3 (#2896)

Bumps [markdown2](https://github.com/trentm/python-markdown2) from 2.4.2 to 2.4.3.
- [Release notes](https://github.com/trentm/python-markdown2/releases)
- [Changelog](https://github.com/trentm/python-markdown2/blob/master/CHANGES.md)
- [Commits](https://github.com/trentm/python-markdown2/compare/2.4.2...2.4.3)

---
updated-dependencies:
- dependency-name: markdown2
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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

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

requirements.txt

@@ -4,7 +4,7 @@ boto3==1.22.4
 imbalanced-learn==0.9.0
 libmozdata==0.1.76
 lmdb==1.3.0
-markdown2==2.4.2
+markdown2==2.4.3
 matplotlib==3.5.1
 mercurial==6.1.1
 microannotate==0.0.24