dist/helm/templates/ingress.yaml:  Fix everything up for Kubernetes versions that support networking.k8s.io/v1/Ingress

src/auth.rs:  Split "business logic" from authenticate() out to a function that returns a simple bool

src/main.rs:  health():  Use query_scalar!() to get back just a single integer, eliminating the need for a type alias

src/main.rs:  Well that's embarrassing; broke the entire UI trying to make the healthcheck work unauthorized and didn't test it properly

.gitlab-ci.yml:  Disable cargo publish for now, since we're relying on a fork of one of our dependencies

.gitlab-ci.yml:  Run `cargo check` instead of `cargo build` to avoid some of the build time; run `cargo build` after everything else runs