Bump mkdocs from 1.5.3 to 1.6.0 (#188)

requirements.txt

@@ -1,7 +1,7 @@
 # This file contains the direct dependencies required for building the docs
 # To install them all run 'pip install -r requirements.txt' in the same directory
 
-mkdocs == 1.5.3
+mkdocs == 1.6.0
 mkdocs-material == 9.5.20
 plantuml-markdown == 3.9.6
 mike == 2.0.0