Update BigBang Pipeline to allow for different values files

he Big Bang pipeline for a MR has 2 deployment phases; clean install and upgrade install. During both of these phases, the same values file (https://repo1.dso.mil/platform-one/big-bang/bigbang/-/blob/master/tests/ci/k3d/values.yaml) is used to setup the phases. To-date we have not needed different values between these phases but the Minio upgrade did use a different set of values between the two phases. In general it is a good infrastructure change to potentially allow different values files for the each phase.