run_tests: stop pinning tempest repo
run_tests: stop pinning tempest repo

We had a workaround due to a new test in
tempest/api/identity/v3/test_projects.py* that used to fail.

This patch aims to drop the pin and come back to master.

* test_list_projects_returns_only_authorized_project

Change-Id: I1ac60e9a5fe8757c7a28b6672df1def3ae6549f8

openstack/puppet-openstack-integration,openstack/puppet-openstack-integration,openstack/puppet-openstack-integration