chore(ci): upgrade mkdocs

Author: dreamorosi

Diff for: docs/requirements.txt

@@ -1,4 +1,4 @@
 mike==1.1.2
-mkdocs-material==9.3.2
+mkdocs-material==9.4.6
 mkdocs-git-revision-date-plugin==0.3.2
 mkdocs-exclude==1.0.2

Diff for: mkdocs.yml

@@ -79,8 +79,8 @@ markdown_extensions:
       toc_depth: 4
   - attr_list
   - pymdownx.emoji:
-      emoji_index: !!python/name:materialx.emoji.twemoji
-      emoji_generator: !!python/name:materialx.emoji.to_svg
+      emoji_index: !!python/name:material.extensions.emoji.twemoji
+      emoji_generator: !!python/name:material.extensions.emoji.to_svg
   - pymdownx.inlinehilite
   - pymdownx.superfences:
       custom_fences: