Update mkdocs dependencies

Author: mdmintz

docs/requirements.txt

@@ -2,10 +2,11 @@ regex>=2020.11.13
 tqdm>=4.56.0
 livereload==2.6.3;python_version>="3.6"
 Markdown==3.3.3
+Jinja2==2.11.3
 readme-renderer==28.0
 pymdown-extensions==8.1.1
 mkdocs==1.1.2
-mkdocs-material==6.2.6
+mkdocs-material==6.2.7
 mkdocs-simple-hooks==0.1.2
 mkdocs-material-extensions==1.0.1
 mkdocs-minify-plugin==0.4.0