MDEV-30953: Add package for Galera server

[illuusio]

• [x] The Jira issue number for this PR is: MDEV-30953

Description

Add new package mariadb-server-galera to Debian to recude mariadb-server package dependencies. Galera cluster scripts and libraries are currently in package mariadb-server. Move Galera cluster scripts and libraries to new package mariadb-server-galera as most of the people does not need them and it allows to slim down mariadb-server package

How can this PR be tested?

As Salsa-CI is currently running out of space most of time (this should be addressed) this could check out: branch: https://salsa.debian.org/illuusio/mariadb-server/-/pipelines/575821 11.3: https://salsa.debian.org/illuusio/mariadb-server/-/pipelines/575819 or build by hand in Debian sid with debian/autobake-deb.sh

This should also go thru MariaDB BB builds

Basing the PR against the correct MariaDB version

• [x ] This is a new feature and the PR is based against the latest MariaDB development branch.

PR quality check

• [x] I checked the CODING_STANDARDS.md file and my PR conforms to this where appropriate.
• [x] For any trivial modifications to the PR, I am ok with the reviewer making the changes themselves.

[illuusio]

Ok no it's working as expected. Galera is turned OFF when it's not installed. What should be done is to ask user or just enable things if Galera package is installed.

[CLAassistant]

All committers have signed the CLA.