Traffic Router does not allow RGB to be enabled on Client steering DSs

[dneuman64]

I'm submitting a ...

• bug report
• new feature / enhancement request
• improvement request (usability, performance, tech debt, etc.)
• other

Traffic Control components affected ...

• CDN in a Box
• Documentation
• Grove
• Traffic Control Client
• Traffic Monitor
• Traffic Ops
• Traffic Ops ORT
• Traffic Portal
• Traffic Router
• Traffic Stats
• Traffic Vault
• unknown

Current behavior:

Currently, Traffic Router does not support regional geo blocking on client steering or client steering target delivery services.

Expected / new behavior:

Traffic Router should allow client steering delivery services to be configured with regional geo-blocking enabled.

Minimal reproduction of the problem with instructions:

setup a steering service
assign targets
configured RGB
send a request
get a 503
check logs and see error message

Anything else:

https://github.com/apache/trafficcontrol/blob/master/traffic_router/core/src/main/java/com/comcast/cdn/traffic_control/traffic_router/core/router/TrafficRouter.java#L753