With mariabackup being renamed to mariadb-backup binary, to keep
some backwards compatability instead of renaming the binary
to call, this patch introduces the whole new strategy designed to
pretty much override only used binary name for modern MariaDB
versions.
This new strategy is selected whenever requested datastore version
is equal or higher 10.4.
This patch is alternative to [1]
[1] https://review.opendev.org/c/openstack/trove/+/948643
Change-Id: I5336c8f98d9f1f33810113b9d7a84f1bef3deb66
bcdec128e4