Expose Preview Branch anon key via CLI

[Thorsten-Kd]

Is your feature request related to a problem? Please describe.
We're creating preview branches for development through a script on the command line. I am able to retrieve all the preview branch details, like the jwt secret, but I am not able to retrieve the anon key via the CLI. We need the anon key to spin up a development server

Describe the solution you'd like
Ideally I would like to use a command like supabase branches get-api-keys <branch_id> that returns the api keys that we can use to spin up a development server.

Describe alternatives you've considered
I tried using the jwt secret returned by supabase branches get <branch_id> to create an anon key, but I wasn't able to create a working anon key even though I followed the directions here and was able to create a similar anon key than the one that is exposed on the dashboard:
https://stackoverflow.com/questions/74587078/any-way-to-generate-supabase-anon-key-and-jwt-secret-locally

Additional context
We need this to be automated and can't copy the anon key manually from the preview branch dashboard.