Complete at least one cycle of regression test with RHCOS 10

To install 4.20 cluster with RHCOS 10, please refer to example jenkins job

override_rhcos_base: "quay.io/openshift-release-dev/ocp-v4.0-art-dev:4.20-10.1-node-image"
override_rhcos_ext: "quay.io/openshift-release-dev/ocp-v4.0-art-dev:4.20-10.1-node-image-extensions" 

We can trigger QE e2e test on this cluster when it is ready.

note: some tests are skipped on Cloud platform so need to run e2e on-premise cluster (vsphere/baremetal) as well.   

update 10/Nov:

To install bare metal cluster with RHCOS 10, please refer to https://github.com/openshift/release/pull/71183 and setup cluster in Prow CI. (jenkins flexy-install doesn't seem to work)