The test in question: tempest/scenario/test_network_advanced_server_ops.py

In assertion of names of flavors there was wrongly used parameter
of name. Instead of server['original_name'] we should use
server['flavor']['original_name'].

Also parameter disk_over_commit in function live_migrate_server
is available until version 2.25[1], so we should check microversion
before using this parameter.

[1] https://docs.openstack.org/api-ref/compute/#live-migrate-server-os-migratelive-action

Reviews:

• https://review.opendev.org/c/openstack/tempest/+/901039