refs https://github.com/TryGhost/Team/issues/1477
- Added default test fixture
- Added tests for validation of newsletter when editing
- Added tests for opening and closing tabs
no issue
The full edit newsletter form with all the settings, design options, and preview felt quite overwhelming when the only piece of data that's required to create a newsletter is the name.
- re-organised the newsletter modal components by renaming `modals/edit-newlsetter` to `modals/newsletters` to better represent the full suite of modals that are used in newsletter management
- added a `modals/newsletters/new` component containing a minimal form with name/description/opt-in-existing fields
- switched the `new-newsletter` route to open the new modal rather than the previous dual-purpose edit modal
- moved message about newsletter creation into the create modal and dropped the separate create confirmation modal
- dropped unnecessary unsaved-changes confirmation
- removed the now-unused opt-in-existing behaviour from the edit newsletter modal
Co-authored-by: Peter Zimon <peter.zimon@gmail.com>
