* Add view test for change submit button
Expect a quoted string for the button values.
* Quote button text in calls to changeSubmitButton
This fixes a parse error (locally now I get an error about not having
a stripe publishing id, which is expected).
* Dark Theme preference is a user setting and not delegated
Resolves NoMethodError
* Add a view spec
This ensures the /credits/purchase page is rendered
* Test both styles based on user setting
Add an actual expectation to the view test