Add new test CDN
When a network is using lancache-dns individual service configuration can be tested using nslookup <service>.cache.lancache.net however if a network is using the generator configs these lancache domains don't exist. This PR adds a new test service for ease of memory for diagnostics
Add new test cdn for the use in testing and diagnostics. Assuming the test service is enabled test.cache.lancache.net and canary.uklans.net will respond with a lancache IP
James Kinsman