Bump tomlkit from 0.5.3 to 0.5.4 in /docs (#108)

Bumps [tomlkit](https://github.com/sdispater/tomlkit) from 0.5.3 to 0.5.4.
- [Release notes](https://github.com/sdispater/tomlkit/releases)
- [Changelog](https://github.com/sdispater/tomlkit/blob/master/CHANGELOG.md)
- [Commits](python-poetry/tomlkit@0.5.3...0.5.4)

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

Author: dependabot-preview[bot]

docs/requirements.txt

@@ -7,7 +7,7 @@ sphinxcontrib-mermaid==0.3.1
 sphinx-typlog-theme==0.7.3
 recommonmark==0.5.0
 m2r==0.2.1
-tomlkit==0.5.3
+tomlkit==0.5.4
 
 # Dependencies of our project:
 typing-extensions==3.7.4