fix(docs): get quickstart guide working again (#31583)

docs/docs/quickstart.mdx

@@ -31,6 +31,9 @@ $ git clone https://github.com/apache/superset
 # Enter the repository you just cloned
 $ cd superset
 
+# Set the repo to the state associated with the latest official version
+$ git checkout tags/4.1.1
+
 # Fire up Superset using Docker Compose
 $ docker compose -f docker-compose-image-tag.yml up
 ```