Add tracing

[jisantuc]

Overview

This PR wires up work done in Raster Foundry's http4s-util subproject to add tracing to the one existing service. Tracing can be configured to point to xray or jaeger currently, but xray doesn't work for a confusing reason (probably because the http4s/circe/etc. versions bump to cats 2.0, see more in notes).

Notes

The broken XRayTracer I think has to do with binary compatibility, but I'm not sure what's causing it in particular. An obvious guess was that since http4s is behind doobie and circe on cats-2.0 upgrades, I'd just need to download everything else, but I get the same error with doobie 0.7 and circe 0.11 as I do with doobie 0.8 and circe 0.12:

java.lang.NoSuchMethodError: 'java.lang.String io.circe.Printer$.apply$default$18()'
    at com.rasterfoundry.http4s.xray.UdpClient$.<init>(UdpClient.scala:11)
    at com.rasterfoundry.http4s.xray.UdpClient$.<clinit>(UdpClient.scala)
    at com.rasterfoundry.http4s.xray.XRayTracingContext$.$anonfun$resource$4(XRayTracingContext.scala:92)
    at cats.effect.internals.IORunLoop$.cats$effect$internals$IORunLoop$$loop(IORunLoop.scala:139)
    at cats.effect.internals.IORunLoop$.start(IORunLoop.scala:34)
    at cats.effect.internals.IOBracket$.$anonfun$apply$1(IOBracket.scala:44)
    at cats.effect.internals.IOBracket$.$anonfun$apply$1$adapted(IOBracket.scala:34)
    at cats.effect.internals.IORunLoop$RestartCallback.start(IORunLoop.scala:341)
    at cats.effect.internals.IORunLoop$.cats$effect$internals$IORunLoop$$loop(IORunLoop.scala:119)
    at cats.effect.internals.IORunLoop$RestartCallback.signal(IORunLoop.scala:355)
    at cats.effect.internals.IORunLoop$RestartCallback.apply(IORunLoop.scala:376)
    at cats.effect.internals.IORunLoop$RestartCallback.apply(IORunLoop.scala:316)
    at cats.effect.internals.IOShift$Tick.run(IOShift.scala:36)
    at java.base/java.util.concurrent.ForkJoinTask$RunnableExecuteAction.exec(ForkJoinTask.java:1426)
    at java.base/java.util.concurrent.ForkJoinTask.doExec(ForkJoinTask.java:290)
    at java.base/java.util.concurrent.ForkJoinPool$WorkQueue.topLevelExec(ForkJoinPool.java:1020)
    at java.base/java.util.concurrent.ForkJoinPool.scan(ForkJoinPool.java:1656)
    at java.base/java.util.concurrent.ForkJoinPool.runWorker(ForkJoinPool.java:1594)
    at java.base/java.util.concurrent.ForkJoinWorkerThread.run(ForkJoinWorkerThread.java:177)

Testing Instructions

• api/assembly
• bring up server
• make some requests to /api/hello/<name>
• look at requests under the granary service in Jaeger on 16686
• change your GRANARY_LOG_LEVEL in docker-compose to INFO
• restart the server
• confirm you don't get a DEBUG message about the jaeger tracing being used

Closes #18

[notthatbreezy]

Looks good to me - I pushed up the changes after our offline discussion on Resource. If you want to clean that up a little more, I say go for it.

Open question on whether to bite the bullet and use log4cats here too