Show stopping environments as well

What does this MR do and why?

To show stopping environments, we rename the scope to Active, as environments are active until they are stopped completely.

Changelog: changed

Screenshots or screen recordings

How to set up and validate locally

1. Navigate to a project's environments page
2. Select New environment and create one
3. Navigate back to the project's environments page
4. Note that it is visible
5. Open the rails console, and force the environment's state to be stopping:

   environment = Environment.last
   environment.state = :stopping
   environment.save!

6. Refresh the project's environments page
7. Note the stopping environment is still visible under Active
8. Set the environment's state to be stopped

   environment = Environment.last
   environment.state = :stopped
   environment.save!

9. Note the environment is now visible under the Stopped tab.

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 #396286 (closed)