Add new environment folder component

What does this MR do and why?

For display of environment folders on the new environments page, and hidden behind the new_environments_table feature flag. It displays the name of the folder, links to it, and is set up to show environments within that folder in upcoming changes.

Screenshots or screen recordings

How to set up and validate locally

1. Enable the new_environments_table feature flag
2. Set up some environments in a folder

MR acceptance checklist

This checklist encourages us to confirm any changes have been analyzed to reduce risks in quality, performance, reliability, security, and maintainability.

• I have evaluated the MR acceptance checklist for this MR.

For #343026 (closed)