Start using pure mariadb in DEB file name and remove version information from name

As now MariaDB Debian package naming scheme is mariadb-10_x.deb. That makes need to add remove all the old versions manually to Debian package installation meta data.
Removing version data from name would make maintenance burden easier and packages would be more like other distributions do it. As now Debian is getting 10.6 in so it would be convinient to start from 10.6 and make change 10.7 and 10.8