Use credhub_admin_client for cats credhub client
Use credhub_admin_client for cats credhub client

[#161032011]

Co-authored-by: Zander Mackie <dad6048958a096c4d96d991a47a426a281ad31ed@pivotal.io>

cloudfoundry/buildpacks-ci,cloudfoundry/buildpacks-ci,cloudfoundry/buildpacks-ci,cloudfoundry/buildpacks-ci,cloudfoundry/buildpacks-ci