Move tutorial sample apps, vote UI: https://github.com/openshift-pipelines/vote-ui/tree/release-tech-preview-2 and Vote API: https://github.com/openshift-pipelines/vote-api/tree/release-tech-preview-2 to supported RH repo

Probably Rick Wagner can guide us on which repos are supported. This conversation needs to start now, so that docs can be modified accordingly in time.
They can be moved to a single repository, if that makes sense.
Can we move it to: https://github.com/openshift/pipelines-tutorial/tree/release-tech-preview-2? repository, which is already under OpenShift, though we might need to get ack from Rick before we do that.