Revert "use the right attr /cc @dblandin"

This reverts commit bd6af92295e44b02c8dcacf9b8ef885b30e23aed.
Revert "Extract last_known_revision logic to Deployment class"
Merge pull request #101 from atmos/revert-100-fix-rubocop-errors

Revert "Extract last_known_revision logic to Deployment class"
Revert "Add commit changes to notifier"
Merge pull request #102 from atmos/revert-95-add-commit-changes-to-notifier

Revert "Add commit changes to notifier"