Replace python-charm-jobs to py3 job
Replace python-charm-jobs to py3 job

python-charm-jobs is py2.7 template which needs
to be replaced by py3. Replacing that with
py35 job and they can move to most recent py3
version once they are ready.

Change-Id: I5269fe2a0f6c5d3a2310b4ade41050e15848615f

openstack-infra/project-config,openstack-infra/project-config