update Runtime Flags reference page to document Ingress Controller support #1963
Description
Page: https://www.pomerium.com/docs/reference/runtime-flags#how-to-configure
What's incorrect or missing
The page states that:
Runtime flags are currently configurable only in Pomerium Core.
However it looks like support was added to Ingress Controller in pomerium/ingress-controller#1010.
What's the resolution?
Let's update the "How to configure" section with an Ingress Controller example and/or a link to the CRD reference.