Update docs dependencies

Author: mdmintz

docs/requirements.txt

@@ -3,15 +3,15 @@ tqdm>=4.60.0
 livereload==2.6.3;python_version>="3.6"
 joblib==1.0.1;python_version>="3.6"
 Markdown==3.3.4
-docutils==0.17
+docutils==0.17.1
 Jinja2==2.11.3
 readme-renderer==29.0
 pymdown-extensions==8.1.1
-importlib-metadata==3.10.1;python_version>="3.6"
+importlib-metadata==4.0.1;python_version>="3.6"
 lunr==0.5.8
 mkdocs==1.1.2
-mkdocs-material==7.1.1
-mkdocs-exclude-search==0.4.0
+mkdocs-material==7.1.2
+mkdocs-exclude-search==0.5.1;python_version>="3.6"
 mkdocs-simple-hooks==0.1.3
 mkdocs-material-extensions==1.0.1
 mkdocs-minify-plugin==0.4.0