fix changelog for single_input

Author: alexcjohnson

CHANGELOG.md

@@ -2,18 +2,17 @@
 All notable changes to `dash` will be documented in this file.
 This project adheres to [Semantic Versioning](https://semver.org/).
 
-## Unreleased
+## [UNRELEASED]
 ### Added
 - [#1315](https://github.com/plotly/dash/pull/1315) Add `update_title` parameter to set or disable the "Updating...." document title during updates. Closes [#856](https://github.com/plotly/dash/issues/856) and [#732](https://github.com/plotly/dash/issues/732)
 
+### Changed
+- [#1180](https://github.com/plotly/dash/pull/1180) `Input`, `Output`, and `State` in callback definitions don't need to be in lists. You still need to provide `Output` items first, then `Input` items, then `State`, and the list form is still supported. In particular, if you want to return a single output item wrapped in a length-1 list, you should still wrap the `Output` in a list. This can be useful for procedurally-generated callbacks.
+
 ## [1.13.4] - 2020-06-25
 ### Fixed
 - [#1310](https://github.com/plotly/dash/pull/1310) Fix a regression since 1.13.0 preventing more than one loading state from being shown at a time.
 
-## [UNRELEASED]
-### Changed
-- [#1180](https://github.com/plotly/dash/pull/1180) `Input`, `Output`, and `State` in callback definitions don't need to be in lists. You still need to provide `Output` items first, then `Input` items, then `State`, and the list form is still supported. In particular, if you want to return a single output item wrapped in a length-1 list, you should still wrap the `Output` in a list. This can be useful for procedurally-generated callbacks.
-
 ## [1.13.3] - 2020-06-19
 
 ## [1.13.2] - 2020-06-18