[BUG] Fix `bin/setup`
[BUG] Fix `bin/setup`

Previously, `bin/setup` was failing when executing `bin/appraisal`,
since the command was run within the dummy app directory.

weggesser/ember-cli-rails,seanpdoyle/ember-cli-rails,rwz/ember-cli-rails,seanpdoyle/ember-cli-rails,weggesser/ember-cli-rails,rwz/ember-cli-rails,thoughtbot/ember-cli-rails,thoughtbot/ember-cli-rails,seanpdoyle/ember-cli-rails,koryteg/glimmer-rails,koryteg/glimmer-rails,thoughtbot/ember-cli-rails,rwz/ember-cli-rails,weggesser/ember-cli-rails,koryteg/glimmer-rails