🐛 Fixed default email recipients always being "everyone" rather than matching post visibility (#16247)

refs https://github.com/TryGhost/Ghost/issues/16125

The previous fix for incorrect recipient details being shown when
re-sending a failed email introduced another bug that prevented the
"Match post visibility" default recipients setting from working.

- the server always sets `post.emailSegment` to `'all'` for new posts so
the publish flow recipient filter logic that checked for
`post.emailSegment` being present always defaulted to `'all'` rather
than falling back to the selected default recipients setting
- when a post has been published but the email failed it will have its
`newsletter` value set so we can use that as a check for using the
`post.emailSegment` value in place of the default recipients setting

ghost/admin/app/utils/publish-options.js

@@ -168,7 +168,7 @@ export default class PublishOptions {
     }
 
     get recipientFilter() {
-        return this.selectedRecipientFilter || this.post.emailSegment || this.defaultRecipientFilter;
+        return this.selectedRecipientFilter || (this.post.newsletter && this.post.emailSegment) || this.defaultRecipientFilter;
     }
 
     get defaultRecipientFilter() {