Fix periodic-neutron-fwaas-pyXX-with-neutron-lib-master jobs
Fix periodic-neutron-fwaas-pyXX-with-neutron-lib-master jobs

These jobs assume the existence of a tools/ostestr_compat_shim.sh file
that does not exist in the neutron-fwaas repository.  This change
creates it.

Change-Id: Iaeaa2067ed4deb1e4c778b562359cc8713aa2a52

openstack/neutron-fwaas,openstack/neutron-fwaas