Limited version range of mkdocs to <2

Author: squidfunk

requirements.txt

@@ -21,7 +21,7 @@
 # Requirements for core
 jinja2>=3.1
 markdown>=3.2
-mkdocs>=1.6
+mkdocs>=1.6,<2
 mkdocs-material-extensions>=1.3
 pygments>=2.16
 pymdown-extensions>=10.2