Add Queue Insights Documentation

[melotic]

To double check:

• [ ] The right tests are in and and the right validation has happened. Guidance: https://github.com/dotnet/arcade/tree/main/Documentation/Validation

This PR adds documentation on Queue Insights.

[riarenas]

@ilyas1974 In case you have any feedback on whether this is a good location for the document.

[garath]

Consider adding a note at the top or at the bottom about how to generally get help. Something like

Please contact the .NET Engineering Services Team with any questions about this service.

[riarenas]

Please contact the .NET Engineering Services Team with any questions about this service.

If anything, Let's move the feedback section to the top then. I really want them to use the submit feedback to ask about this instead of random questions through other communication channels.

[garath]

Looks great to me! None of my comments are deal-breakers. Good work.

[melotic]

Thanks for the feedback :)