Add support for OpenTelemetry Java Instrumentation 2.0.0+

[ThomasVitale]

Describe the Enhancement

The new major release train of OpenTelemetry Java Instrumentation introduces several breaking change. This enhancement is to prepare a new major release of this buildpack to add support for it, and handle carefully the release process to avoid affecting existing users of this buildpack.

Release notes: https://github.com/open-telemetry/opentelemetry-java-instrumentation/releases/tag/v2.0.0

Context

See: https://github.com/paketo-buildpacks/opentelemetry/pull/112

[anthonydahanne]

@ThomasVitale @dmikusa Hello 👋 May is in a month, should we switch the library now and bump the major to 2 ?

[ThomasVitale]

@anthonydahanne yeah, it seems a good time for that. I'll start working on this and submit a PR soon

[tudburley]

Hi, is there any time schedule when the update to OpenTelemetry 2.4 will be done? As mentioned here, OTel 1.32.x is only supported until May.

[ThomasVitale]

@tudburley As soon as this PR is merged, we should be able to cut a new release: https://github.com/paketo-buildpacks/opentelemetry/pull/132 @dmikusa what do you think?

[dmikusa]

Hi all, we've released paketo-buildpacks/opentelemetry@2.0.0 which has the 2.4.0 agent. Please give it a try and let me know if you have any issues.

@ThomasVitale thanks for the PR!

[ThomasVitale]

@dmikusa great, thank you!

I took the chance to update the OpenTelemetry sample here and test the new buildpack version with the current version of Spring Boot: https://github.com/paketo-buildpacks/samples/pull/738

[StefanLobbenmeierObjego]

FYI there is a slight breaking change in opentelemetry v2, because it changed from http to grpc by default. We export to tempo, so it was just a matter of replacing the OTEL_EXPORTER_OTLP_ENDPOINT port from 4317 to 4318