Consolidate `bigbang.dev` cert for CI/Dev

Currently when we have to update the cert there are 6+ places...

• https://repo1.dso.mil/platform-one/big-bang/bigbang/-/blob/master/chart/ingress-certs.yaml
• https://repo1.dso.mil/platform-one/big-bang/bigbang/-/blob/master/chart/keycloak-dev-values.yaml#L53
• https://repo1.dso.mil/platform-one/big-bang/bigbang/-/blob/master/tests/ci/keycloak-certs/keycloak-passthrough-values.yaml
• https://repo1.dso.mil/platform-one/big-bang/bigbang/-/blob/master/tests/ci/secrets/ingress-cert.yaml
• https://repo1.dso.mil/platform-one/big-bang/bigbang/-/blob/master/hack/secrets/ingress-cert.yaml
• https://repo1.dso.mil/platform-one/big-bang/customers/template/-/blob/main/base/bigbang-dev-cert.yaml

It's unclear which of these are required and what each are required for. Since we have the cert in plaintext in the repo it seems pointless to have the encrypted license required for CI. Ideally we have CI point to the same values files in the helm command as are used by developers. While we may still need to have two separate files for keycloak/normal ingress (maybe?) we should be able to make this a max of 2 or 3 files (since the customer template has its own - does this cert even belong in the customer template?).

AC:

• certs consolidated down to a minimum number of files
• cert update process documented so it's easy to know each spot for updating