Update CHANGELOG.md

Author: keveleigh

org.mixedrealitytoolkit.input/CHANGELOG.md

@@ -4,6 +4,10 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.1.0/).
 
 ## Unreleased
 
+### Added
+
+* Added a test for multiple/single selection of `StatefulInteractable` and its various modes. [PR #1069](https://github.com/MixedRealityToolkit/MixedRealityToolkit-Unity/pull/1069)
+
 ### Changed
 
 * Reserialized MRTK XR Rig prefab to remove stale serialized fields. [PR #1110](https://github.com/MixedRealityToolkit/MixedRealityToolkit-Unity/pull/1110)
@@ -48,7 +52,7 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.1.0/).
 
 ### Fixed
 
-* Fixed missing [CanEditMultipleObject] attributes as per Bug 573 [PR #698](https://github.com/MixedRealityToolkit/MixedRealityToolkit-Unity/pull/698)
+* Fixed missing \[CanEditMultipleObject\] attributes as per Bug 573 [PR #698](https://github.com/MixedRealityToolkit/MixedRealityToolkit-Unity/pull/698)
 * Add logic to account for a bound but untracked interaction profile. [PR #704](https://github.com/MixedRealityToolkit/MixedRealityToolkit-Unity/pull/704)
 * Reduced package description to support for UPM package publishing in the Unity Asset Store.
 * Ensures the simulated input sources hold their state (including gestures) when their toggle state is locked on. [PR #705](https://github.com/MixedRealityToolkit/MixedRealityToolkit-Unity/pull/705)