As an editor, I want a checkbox in the post-edit dialog to stop seeing it, so that I don't have to hunt through preferences to turn it off.
Context: The dialog currently points users to preferences, which is hard to find.

Proposed design

1. Users can click a new option on the popover that reads "Don't show this again"	2. If the user clicks on "Don't show this again", the popover is removed and a message comes up about the possibility of turning it back on in Preferences

(Copy for the message TBD, we can refine)

Acceptance criteria:

• If a user is prompted with an event promotion dialog, they should see a secondary, quiet, neutral "Don't show this again" button
• If the user clicks on "Don't show this again", then they see a message communicating that the promotion dialog has been turned off, and that they can turn it back on through Preferences.