Deprecates tracing support for dependencies not released in 1.5-3.5+ years

[codefromthecrypt]

This deprecates for removal the following, as they have not been updated in a long time. The exception to this rule is log4j context, which is widely used even if not updated recently.

• context/rxjava2 - last released Feb 2021
  • replaced by RxJava3, but unlikely this module will be ported as it wasn't used widely.
• instrumentation/dubbo-rpc - (alibaba) last released Dec 2021
  • replaced by Apache Dubbo instrumentation/dubbo
• instrumentation/p6spy - last released July 2020
  • project dormant
• instrumentation/sparkjava - last released July 2022
  • project dormant

These will be removed in Brave 6 and can be re-introduced if something changes.

[codefromthecrypt]

opened #1394 about the flakey artemis invoker test

[codefromthecrypt]

not sure why, but didn't flake this time.