Add charset number to system catalog

When MCOL-4580 was started it is believed that information given by MariaDB's server is sufficient for our purposes. But, it is not.

INSERT operations, right now, are given charset numbers but not actual collation. And if collations for database differ, we get wrong ranges in MCOL-4580 (linked) which leads to incorrect SELECT results.

The cpimport utility does not have collation information at all and it should receive it from system catalog queries.

All-in-all, we need to store in system catalog either pair (charset index, collation index) or just collation index (it appears it is possible to deduce charset index from it) and provide API to fetch these.

[Note for the documentation team]:
Upgrade instructions from previous versions of ColumnStore to a version with this feature:
dbbuilder should perform an automatic upgrade of the system catalog. When the package manager starts the ColumnStore services using systemd during installation, dbbuilder is executed.
After the upgrade, sanity testing should be performed on the installation to ensure the existing database is not impacted in any way.