Add glance image import web-download tests

Glance image can be imported with web-download
import method
- https://docs.openstack.org/api-ref/image/v2/index.html#interoperable-image-import

Depends-On: https://review.opendev.org/#/c/742574/
Change-Id: I6f30f6fd0e63d83a7abac4eccc2a8ad57365a7ce
2 files changed