Update tracing documentation to use the Java agent

[lvanengelen]

In Mendix 10.19.0 we moved to handling tracing configuration through the OpenTelemetry Java Agent. Update the documentation to reflect that change.

This change is targeted for the 10.19.0 release.

[MarkvanMents]

Thanks for the PR @lvanengelen.
I've put back in the stuff for 10.18 as this is an MTS and customers are likely to be using it until 10.24 comes out.
Approving, but please check if you have any concerns and I can update it before next week.

[lvanengelen]

Thanks for the PR @lvanengelen. I've put back in the stuff for 10.18 as this is an MTS and customers are likely to be using it until 10.24 comes out. Approving, but please check if you have any concerns and I can update it before next week.

Thank you @MarkvanMents , putting it back makes sense. I added some small comments.

[MarkvanMents]

Thanks for the review @lvanengelen
All good points and I have made the changes you suggest.
All ready to be published with 10.19.