[controller] Add LVMVolumeGroupSet

[ViktorKram]

Description

LVMVolumeGroupSet - is a special CR, that allows to create several LVMVolumeGroup resources at once by a common template.
To achieve that, users should create or update LVMVolumeGroupSet specified the desired LVMVolumeGroup resources creation strategy, nodes and blockDeviceSelector. The controller will automatically create LVMVolumeGroups and fill them with desired configuration.

Note, that for now there is only one LVMVolumeGroup creation strategy - PerNode. That means only one LVMVolumeGroup resource will be created on a single node, so in this case, the total amount of the LVMVolumeGroup resources will be the same as specified nodes by nodeSelector in LVMVolumeGroupSet.

Why do we need it, and what problem does it solve?

No more copy-pasta LVMVolumeGroup resources configuration.
Much more user-friendly and faster way to create LVMVolumeGroups.

What is the expected result?

LVMVolumeGroup resources are created by the LVMVolumeGroupSet and got in a Ready state.

Checklist

• The code is covered by unit tests.
• e2e tests passed.
• Documentation updated according to the changes.
• Changes were tested in the Kubernetes cluster manually.