Vendor @fastify/otel instrumentation #16309
Description
Description
We forked @fastify/otel before to downgrade its OpenTelemetry dependencies to v1 to match those of our SDKs. This came with issues on its own: #16281, #16300
Both pnpm and yarn v3 have issues with the way we specify the url to the fork, therefore we should switch strategy and vendor the instrumentation in.
Related to #16311