We're currently deploying 10.2.17 which is quite old and we seem
to be having issues in the gate with some database sync's causing
MariaDB to crash, as well as personal experience with similar
crashes around Cinder database syncs
In addition, this change implements the usage of mariabackup for
SST transfers which eliminates the need for the Percona repos.
The compression is no longer recommended by upstream now, therefore,
we remove it.
Change-Id: I59a0e225205be43b5bfc76c4bc3381b6e9c54cfd
94640cd215