cmd/{k8s-operator,containerboot}: check TLS cert before advertising VIPService
- Ensures that Ingress status does not advertise port 443 before
TLS cert has been issued
- Ensure that Ingress backends do not advertise a VIPService
before TLS cert has been issued, unless the service also
exposes port 80
Updates tailscale/corp#24795
Signed-off-by: Irbe Krumina <irbe@tailscale.com>