iTwin Reality Data - add GeoJSON/KML support

[jjspace]

Description

This is a follow up to #12334 to add support for GeoJSON and KML data types from the Reality Management API.

The implementation should be good to go but the Sandcastle will need updated to the iTwin and data we actually want to use.

• [ ] Updated Sandcastle data

Issue number and link

No issue

Testing plan

• Check the new iTwin Feature Service sandcastle and make sure all data is loading as expected

Author checklist

• [ ] I have submitted a Contributor License Agreement
• [ ] I have added my name to CONTRIBUTORS.md
• [ ] I have updated CHANGES.md with a short summary of my change
• [ ] I have added or updated unit tests to ensure consistent code coverage
• [ ] I have updated the inline documentation, and included code examples where relevant
• [ ] I have performed a self-review of my code

[github-actions[bot]]

Thank you for the pull request, @jjspace!

:white_check_mark: We can confirm we have a CLA on file for you.

[jjspace]

Thanks for the review @jjhembd!

I guess we want to wait for the final data before merging?

That is correct. The code shouldn't change but I will change the iTwin and specific reality data assets the sandcastle is pointing at before this is ready to merge