- for keys use Composer-Test-Key prefix (for consistency)
- for images and VMs use Composer-Test prefix
- delete VMs both by searching by tags & by name in case we
manually create them without tags
The OS_PROJECT_NAME (or OS_TENANT_NAME) environment variable needs to be defined.
Use the OS_PROJECT_NAME, since it is recommended in the documentation instead of
the older OS_TENANT_NAME.
