decide what to do for fastify auto-instrumentation

[trentm]

OTel JS contrib has instr-fastify for v3, v4, v5. It is being deprecated, disabled by default in auto-instrumentations-node and will eventually be removed in favour of fastify/otel (from the fastify community). The new fastify/otel supports only v5 for now. It is also not auto-instrumentation: the user must manually await fastifyApp.register(fastifyInstrumentation.plugin());

This issue is about what we want EDOT Node.js to do for fastify instrumentation.