build(deps): bump pyyaml from 5.3.1 to 5.4 (#98)

Bumps [pyyaml](https://github.com/yaml/pyyaml) from 5.3.1 to 5.4.
- [Release notes](https://github.com/yaml/pyyaml/releases)
- [Changelog](https://github.com/yaml/pyyaml/blob/master/CHANGES)
- [Commits](yaml/pyyaml@5.3.1...5.4)

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

Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>
Co-authored-by: Alex Kanitz <alexander.kanitz@unibas.ch>

requirements.txt

@@ -13,7 +13,7 @@ PyJWT==1.7.1
 pylint==2.5.3
 pymongo==3.10.1
 pytest==5.4.3
-PyYAML==5.3.1
+PyYAML==5.4
 requests==2.23.0
 swagger-ui-bundle==0.0.6
 toml==0.10.0