Remove remove subscriber list "let" statement
Remove remove subscriber list "let" statement

This isn't used as part of the test - a fixture is returned instead [1].

[1]: https://github.com/alphagov/finder-frontend/blob/4ecc0b352f83461afd44e64438a4a59f0ecb6c39/spec/features/brexit_checker/save_results_spec.rb#L62

alphagov/finder-frontend,alphagov/finder-frontend,alphagov/finder-frontend,alphagov/finder-frontend