Interested parties file linked at multiple places, but deleted

[fharper]

The Interested parties file is linked at multiple places, but it was deleted. Since I don't know if the link or text relating to the file needs to be updated, or if the file deletion was a mistake, I'm creating this issue to sort this out :)

Happy to do a PR once I know what to do or let someone from the proper committee do it.

[scottrigby]

Thank you @fharper I only just noticed this looking at it for a different reason.

To-do: address this in OpenGitOps. WG meeting topic, and if needed maintainer meeting to decide how to address. I have some suggestions and important considerations in this comment https://github.com/cncf/tag-app-delivery/pull/256#issuecomment-1462693018