Add comment about Zone.js Promise override in documentation

[tskarhed]

Description

If libraries override default browser globals, I want to know why so I can make an informed decision if it is something I'd want to do.

Proposed solution

Add a short information box to the tracing instrumentation documentation explaining that it overrides Promises and why that is needed (maybe a link to some otel page that explains it?)

Context

Grafana 11.2 was released and we had no idea that Promises were overridden.