NGINX v1.23 concatenates duplicate headers into a single comma-separated string. We were doing an equality check on `x-forwarded-proto`. If the request includes multiple `x-forwarded-proto` headers then this check would fail under NGINX v1.23, and our config assumed an `http` connection.
This commit updates the config to check for `https` at the end of the header, thereby restoring the old behavior when multiple `x-forwarded-proto` request headers are sent.