It adds support for starting, stopping, and restarting VirtualMachines.
The operations are performed through the KubeVirt restart subresource
API (PUT to `subresources.kubevirt.io/v1`). These calls are extracted
into a single shared helper function `_call_subresource()` to handle the
common flow, i.e., check mode, API call and wait conditions.
Moreover, it adds the optional parameter `grace_period_seconds` for
stop and start operations.
Additionally, it adds unit tests and integration tests for all
operations.
Assisted-by: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
Signed-off-by: Javier Cano Cano <jcanocan@redhat.com>