Bump charset-normalizer from 2.0.3 to 2.0.4 (#340)

Bumps [charset-normalizer](https://github.com/ousret/charset_normalizer) from 2.0.3 to 2.0.4.
- [Release notes](https://github.com/ousret/charset_normalizer/releases)
- [Commits](Ousret/charset_normalizer@2.0.3...2.0.4)

---
updated-dependencies:
- dependency-name: charset-normalizer
  dependency-type: indirect
  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>

docs-requirements.txt

@@ -12,7 +12,7 @@ certifi==2021.5.30
     # via requests
 cffi==1.14.5
     # via cryptography
-charset-normalizer==2.0.3
+charset-normalizer==2.0.4
     # via requests
 cryptography==2.9.2
     # via -r docs-requirements.in