Remove openstack-common.conf
Remove openstack-common.conf

This commit removes openstack-common.conf file. Because we don't use
openstack/common files anymore.

Change-Id: I4654a7cd5be6164f7e5ab6fe683f226713ffc3f8

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