Bump Python requirement mkdocs to 1.5.2

docs-requirements.txt

 black==23.7.0
 doc8==1.1.1
-mkdocs==1.4.3
+mkdocs==1.5.2
 mkdocs-material==9.1.14
 mkdocstrings==0.21.2
 mkdocstrings-python==1.3.0