Launchpad: #1911011
Gerrit review: https://review.opendev.org/c/openstack/charm-nova-compute/+/783371
* Functional tests for `instance-count` action on nova-compute charm.
Test for `remove_from_cloud_actions` waits at the end until
the nova-compute service is available again. However there's a few
seconds lag until that host shows up also in `hypervisor-list` which
can cause race conditions with other tests.