feat(vm): hotplug cpu (phase 1)

[diafour]

Description

• Simple implementation of CPU hotplug.

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

What is the expected result?

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.

Changelog entries

section: vm
type: feature
summary: "Simple implementation of CPU hotplug"