message: chore(otel): Update README to add alpha note
diff: [![npm dm](https://img.shields.io/npm/dm/@sentry/opentelemetry-node.svg)](https://www.npmjs.com/package/@sentry/opentelemetry-node)
  [![npm dt](https://img.shields.io/npm/dt/@sentry/opentelemetry-node.svg)](https://www.npmjs.com/package/@sentry/opentelemetry-node)
  +This package allows you to send your NodeJS OpenTelemetry trace data to Sentry via OpenTelemetry SpanProcessors.
  +
  +This SDK is **considered experimental and in an alpha state**. It may experience breaking changes. Please reach out on
  +[GitHub](https://github.com/getsentry/sentry-javascript/issues/new/choose) if you have any feedback/concerns.
  +
  ## Installation
  ```bash
  @@ -55,7 +60,3 @@ otelApi.propagation.setGlobalPropagator(new SentryPropagator());
  ## Links
  - [Official SDK Docs](https://docs.sentry.io/quickstart/)
  -
  -## Usage
  -
  -TODO
  