Add admin list_servers test with invalid_status
Add admin list_servers test with invalid_status

This test is for reproducing the problem of bug/1579706 on the gate
test.

Change-Id: Ib94e9250555d627e71a1f96ae0e82fe58e084fd6
Depends-On: I10bde78f0a9ac59b8646d58f62fa5056f989f54f
Related-Bug: #1579706

Tesora/tesora-tempest,openstack/tempest,vedujoshi/tempest,masayukig/tempest,sebrandon1/tempest,Tesora/tesora-tempest,cisco-openstack/tempest,openstack/tempest,cisco-openstack/tempest,masayukig/tempest,vedujoshi/tempest,sebrandon1/tempest,Juniper/tempest,Juniper/tempest