coordination #42854: [functional][y][epic] Introduce relevant installation validation test modules
[y] Add validation to multipath scenario
See motivation in the parent ticket.
With multipath enabled, we just check if system boots, but it can be the case that installer doesn't enable it properly, so we should validate partitioning at least.
It also would make sense to do some sanity checks for the default parameters.
For some cli examples: https://access.redhat.com/documentation/en-us/red_hat_enterprise_linux/5/html/dm_multipath/multipath_queries
- Partitioning is validated for multipath scenario
- Test plan is updated accordingly