Build(deps): bump bleach from 3.1.0 to 3.3.0

Bumps [bleach](https://github.com/mozilla/bleach) from 3.1.0 to 3.3.0.
- [Release notes](https://github.com/mozilla/bleach/releases)
- [Changelog](https://github.com/mozilla/bleach/blob/master/CHANGES)
- [Commits](https://github.com/mozilla/bleach/compare/v3.1.0...v3.3.0)

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

requirements.txt

@@ -1,7 +1,7 @@
 appdirs==1.4.3
 attrs==19.3.0
 black==19.10b0
-bleach==3.1.0
+bleach==3.3.0
 blessings==1.7
 certifi==2019.11.28
 cffi==1.13.2