docs(README): update link to @opentelemetry/api package (#2263)

Co-authored-by: Bartlomiej Obecny <bobecny@gmail.com>
Co-authored-by: Daniel Dyla <dyladan@users.noreply.github.com>

README.md

@@ -426,7 +426,7 @@ Apache 2.0 - See [LICENSE][license-url] for more information.
 [otel-shim-opentracing]: https://github.com/open-telemetry/opentelemetry-js/tree/main/packages/opentelemetry-shim-opentracing
 [otel-tracing]: https://github.com/open-telemetry/opentelemetry-js/tree/main/packages/opentelemetry-tracing
 [otel-web]: https://github.com/open-telemetry/opentelemetry-js/tree/main/packages/opentelemetry-web
-[otel-api]: https://github.com/open-telemetry/opentelemetry-js/tree/main/packages/opentelemetry-api
+[otel-api]: https://github.com/open-telemetry/opentelemetry-js-api
 [otel-core]: https://github.com/open-telemetry/opentelemetry-js/tree/main/packages/opentelemetry-core
 [generate-api-documentation]: https://github.com/open-telemetry/opentelemetry-js/blob/main/CONTRIBUTING.md#generating-api-documentation