The ingress api version changed when it went to v1, and this has caused some upheaval
throughout the kubernetes ecosystem. This commit uses a common method of deciding which
ingress api to use, and allows the optional override of the kubernetes version
presented to helm using the helm build-in capabilities.
also add an ingress into the helm integration tests so any regressions to how ingresses
are handled in the future are caught easier.
Closes rook#9174
Signed-off-by: Tom Hellier <me@tomhellier.com>