Update notes for submitted changes

* GRIND-47: Migration tests don't need agent.
Update notes for submitted changes

* GRIND-47: Migration testing shouldn't exclude Windows
Update notes for submitted changes

* GRIND-47: Allow to boot on specific host.
Update notes for submitted changes

* GRIND-47: Helper to assert a host supports Cobalt hooks
Update notes for submitted changes

* GRIND-47: Helper to drop a Cobalt hook on a host.