docs(tracer): add notice about adot (#1581)

Author: dreamorosi

docs/core/tracer.md

@@ -22,6 +22,8 @@ Tracer is an opinionated thin wrapper for [AWS X-Ray SDK for Node.js](https://gi
 
 ## Getting started
 
+!!! note "Tracer relies on AWS X-Ray SDK over [OpenTelememetry Distro (ADOT)](https://aws-otel.github.io/docs/getting-started/lambda){target="_blank"} for optimal cold start (lower latency)."
+
 ### Installation
 
 Install the library in your project: