When running galera_server role with galera_upgrade=true
it uninstalls mariadb and installs again. In some distros, like CentOS,
mariadb don't start automatically after installation, so upgrade fails.
This patch adds handler on packsage installation, which will be
triggered when package state is changed.
Change-Id: I23811cfaf23007c5da1860e78397be380d67403b
Related-bug: 1628720