Chore: Move to ubuntu2004-builder

Chore: Move to ubuntu2004-builder

jjb/usecaseui/usecase-ui-nlp.yaml
jjb/usecaseui/usecase-ui-server.yaml
jjb/usecaseui/usecase-ui.yaml
jjb/vfc/vfc-gvnfm-vnflcm-java.yaml
jjb/vfc/vfc-gvnfm-vnflcm-python.yaml
jjb/vfc/vfc-gvnfm-vnfmgr-java.yaml
jjb/vfc/vfc-gvnfm-vnfmgr-python.yaml
jjb/vfc/vfc-gvnfm-vnfres-java.yaml
jjb/vfc/vfc-gvnfm-vnfres-python.yaml
jjb/vfc/vfc-nfvo-db.yaml
jjb/vfc/vfc-nfvo-driver-svnfm-huawei.yaml
jjb/vfc/vfc-nfvo-driver-vnfm-gvnfm-java.yaml
jjb/vfc/vfc-nfvo-driver-vnfm-gvnfm-python.yaml
jjb/vfc/vfc-nfvo-driver-vnfm-svnfm-docker-java.yaml
jjb/vfc/vfc-nfvo-driver-vnfm-svnfm-root.yaml

Issue-ID: CIMAN-33
Signed-off-by: Bengt Thuree <bthuree@linuxfoundation.org>
Change-Id: I0e52e1d9c8148718a9e9f2ca7256301ca9517c9d