Bump bleach from 3.3.1 to 4.0.0 (#88)

Bumps [bleach](https://github.com/mozilla/bleach) from 3.3.1 to 4.0.0.
- [Release notes](https://github.com/mozilla/bleach/releases)
- [Changelog](https://github.com/mozilla/bleach/blob/main/CHANGES)
- [Commits](https://github.com/mozilla/bleach/compare/v3.3.1...v4.0.0)

---
updated-dependencies:
- dependency-name: bleach
  dependency-type: direct:development
  update-type: version-update:semver-major
...

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

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

requirements-dev.txt

@@ -1,4 +1,4 @@
-bleach==3.3.1
+bleach==4.0.0
 bump2version==1.0.1
 bumpversion==0.6.0
 certifi==2021.5.30