Goal:

Add a Tempest test to verify expected behaviour when using Swift staticweb with prefix-based tempurls, added in https://github.com/openstack/swift/commit/8c4e65a6 

Acceptance Criteria:

Test proposed upstream and at least one +1 review (excluding CI reviews).

Note:

There are existing tests in Tempest; the test for prefix-based tempurls should be added there as well: https://github.com/openstack/tempest/blob/master/tempest/api/object_storage/test_container_staticweb.py 

Documentation on the staticweb feature can be found at https://docs.openstack.org/swift/latest/api/static-website.html and https://docs.openstack.org/swift/latest/middleware.html#staticweb