Update dependency mkdocs to v1.4.3 (#119)

Author: slack-oss-bot

.github/workflows/mkdocs-requirements.txt

@@ -5,7 +5,7 @@ livereload==2.6.3
 lunr==0.6.2
 Markdown==3.4.3
 MarkupSafe==2.1.2
-mkdocs==1.4.2
+mkdocs==1.4.3
 mkdocs-macros-plugin==0.7.0
 mkdocs-material==9.1.8
 mkdocs-material-extensions==1.1.1