Update dependency mkdocs-material to v9.2.1 (#21)

Co-authored-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>

Author: renovate[bot]

.mkdocs/requirements.txt

@@ -1,5 +1,5 @@
 mkdocs-git-revision-date-localized-plugin==1.2.0
-mkdocs-material==9.1.21
+mkdocs-material==9.2.1
 mkdocs-autolinks-plugin==0.7.1
 mkdocs-diagrams==1.0.0
 mkdocs-glightbox