[docs] Add Superset documentation to /clients/

[steveburnett]

Description

Add documentation how to configure Apache Superset to connect to Presto.

Motivation and Context

Expands the number of clients documented for use with Presto. Builds on recent work in #23189.

Impact

Documentation.

Test Plan

• Tested and developed the steps in the documentation with a locally running Presto server and a locally running Superset instance.
• Tested the documentation with a local doc build.

Contributor checklist

• Please make sure your submission complies with our development, formatting, commit message, and attribution guidelines.
• PR description addresses the issue accurately and concisely. If the change is non-trivial, a GitHub Issue is referenced.
• Documented new properties (with its default value), SQL syntax, functions, or other functionality.
• If release notes are required, they follow the release notes guidelines.
• Adequate tests were added if applicable.
• CI passed.

Release Notes

Please follow release notes guidelines and fill in the release notes below.

== RELEASE NOTES ==

General Changes
* ... Add :doc:`/clients/superset` documentation :pr:`23194`

[steveburnett]

Addressed @elharo's suggestions, merged commits, and pushed - which dismissed the two previous approvals.