the HTTPS redirect route may cause non-deterministic route matching in Kubernetes

[aryszka]

the HTTPS redirect feature was implemented before the custom predicates from the ingress annotations. In the redirect route we apply an assumption about the number of predicates:

	// the forwarded port and any-path (.*) is set to make sure that
	// the redirect route has a higher priority during matching than
	// the normal routes that may have max 2 predicates: path regexp
	// and host.

...that is not valid anymore. For explanation why the number of predicates matters, see the "Route matching" section.

One solution to this problem can be the solution outlined in this issue: https://github.com/zalando/skipper/issues/360

[szuecs]

I think this was fixed with https://github.com/zalando/skipper/pull/1877 wdyt @aryszka ?