Update tomlkit from 0.5.7 to 0.5.8

docs/requirements.txt

@@ -7,7 +7,7 @@ sphinxcontrib-mermaid==0.3.1
 recommonmark==0.6.0
 m2r==0.2.1
 added-value==0.14.2
-tomlkit==0.5.7
+tomlkit==0.5.8
 docutils==0.14
 
 # Dependencies of our linter that should be documented,