Chore: Move to ubuntu2004-builder

Chore: Move to ubuntu2004-builder

jjb/oparent/oparent.yaml
jjb/openci/openci-onap-daily-jobs.yaml
jjb/optf/optf-has.yaml
jjb/optf/optf-osdf.yaml
jjb/policy/policy-apex-pdp.yaml
jjb/policy/policy-api.yaml
jjb/policy/policy-common.yaml
jjb/policy/policy-distribution.yaml
jjb/policy/policy-docker-base-common.yaml
jjb/policy/policy-drools-applications.yaml
jjb/policy/policy-drools-pdp.yaml
jjb/policy/policy-gui.yaml
jjb/policy/policy-models.yaml
jjb/policy/policy-pap.yaml
jjb/policy/policy-parent.yaml

Issue-ID: CIMAN-33
Signed-off-by: Bengt Thuree <bthuree@linuxfoundation.org>
Change-Id: I24b0b9e869e30a222c76fd9159b3b215cce7e9de