When a user runs the install.sh script, they get the latest version of the Sentry, Snuba, Relay and Symbolicator projects. However there is no guarantee they have pulled the latest self-hosted version first, and running an old one may cause problems. To mitigate this, we now perform a check during installation that the user is on the latest commit if they are on the master branch. You can disable this check with --skip-commit-check.