modify test-requirement according to requirements project
modify test-requirement according to requirements project

the OpenStack requirements project has modify version requirement of docutils/oslosphinx.
The link is below
https://review.openstack.org/#/c/418772/
So modify test-requirement like other project
Closes-Bug: #1666149

Change-Id: I6a3b2e0a30333a84a8350f2ba5f53acaccd94ebb

stackforge/refstack-client,stackforge/refstack-client,openstack/refstack-client,openstack/refstack-client