Fix docs build issue
Fix docs build issue

For some reason docs builds break when using the sphinx version listed.
Just use the same one as the rest of OpenStack.

Also - while we're at it - setuptools_git hasn't been a thing in a LONG
time.

Change-Id: I70d45f5b237ceb9b67ca4ce458816f41a197d228

rsig/jenkins-job-builder,onshape/jenkins-job-builder,dataxu/jenkins-job-builder,OSSystems/jenkins-job-builder,dataxu/jenkins-job-builder,phinexus/jenkins-job-builder,gforcada/jenkins-job-builder,twc-openstack/jenkins-job-builder,wikimedia/integration-jenkins-job-builder,twc-openstack/jenkins-job-builder,rsig/jenkins-job-builder,puppetlabs/jenkins-job-builder,wsoula/jenkins-job-builder,gforcada/jenkins-job-builder,onshape/jenkins-job-builder,dataxu/jenkins-job-builder,OSSystems/jenkins-job-builder,phinexus/jenkins-job-builder,OSSystems/jenkins-job-builder,tamac-io/jenkins-job-builder,phinexus/jenkins-job-builder,twc-openstack/jenkins-job-builder,onshape/jenkins-job-builder,tamac-io/jenkins-job-builder,rsig/jenkins-job-builder,tamac-io/jenkins-job-builder,gforcada/jenkins-job-builder,phinexus/jenkins-job-builder,wikimedia/integration-jenkins-job-builder,puppetlabs/jenkins-job-builder,phinexus/jenkins-job-builder,puppetlabs/jenkins-job-builder,puppetlabs/jenkins-job-builder,wsoula/jenkins-job-builder,tamac-io/jenkins-job-builder,OSSystems/jenkins-job-builder,onshape/jenkins-job-builder,gforcada/jenkins-job-builder,wikimedia/integration-jenkins-job-builder,dataxu/jenkins-job-builder,wsoula/jenkins-job-builder,wikimedia/integration-jenkins-job-builder,rsig/jenkins-job-builder,twc-openstack/jenkins-job-builder,wsoula/jenkins-job-builder,gforcada/jenkins-job-builder,wikimedia/integration-jenkins-job-builder