Handle block quote like list item in editor

In the editor, if you are editing a list item and you git return, you get a new line that starts with a list item marker. Hit return again without typing further on the live and you get another new line and the item markers disappear.

I like this.

In contrast, if you're in a block quote, new lines will all have the indicator at their starts (>), no matter that the line had nothing in it.

I don't like this and suggest modifying the behavior of the editor in block quotes to match that in lists.