docs: Update docs builder image (#3516)

- Bump to release `9.2.x`
- Image now has `MAJOR.MINOR` tag support to pull latest `PATCH` versions.

.github/workflows/scripts/docs/build-docs.sh

@@ -10,7 +10,7 @@ docker run \
   --user "$(id -u):$(id -g)" \
   --volume "${PWD}:/docs" \
   --name "build-docs" \
-  squidfunk/mkdocs-material:9.1.5 build --strict
+  squidfunk/mkdocs-material:9.2 build --strict
 
 # Remove unnecessary build artifacts: https://github.com/squidfunk/mkdocs-material/issues/2519
 # site/ is the build output folder.