[unity] Added CHANGELOG entry for previous commit 1b8a378 (Timeline: Added SpineAnimationStateClip holdPrevious parameter).

CHANGELOG.md

@@ -241,6 +241,7 @@
   * Added `Root Motion Scale X/Y` parameters to `SkeletonRootMotionBase` subclasses (`SkeletonRootMotion` and `SkeletonMecanimRootMotion`). Also providing `AdjustRootMotionToDistance()` and other methods to allow for easy delta compensation. Delta compensation can be used to e.g. stretch a jump to a given distance. Root motion can be adjusted at the start of an animation or every frame via `skeletonRootMotion.AdjustRootMotionToDistance(targetPosition - transform.position, trackIndex);`.
   * Now providing a `Canvas Group Tint Black` parameter at the `SkeletonGraphic` Inspector in the `Advanced` section. When using the `Spine/SkeletonGraphic Tint Black` shader you can enable this parameter to receive proper blending results when using `Additive` blend mode under a `CanvasGroup`. Be sure to also have the parameter `CanvasGroup Compatible` enabled at the shader. Note that the normal `Spine/SkeletonGraphic` does not support `Additive` blend mode at a `CanvasGroup`, as it requires additional shader channels to work.
   * Added `Mix and Match Skins` example scene to demonstrate how the 3.8 Skin API and combining skins can be used for a wardrobe and equipment use case.
+  * Spine Timeline Extensions: Added `Hold Previous` parameter at `SpineAnimationStateClip`.
 
 * **Changes of default values**
   * `SkeletonMecanim`'s `Layer Mix Mode` now defaults to `MixMode.MixNext` instead of `MixMode.MixAlways`.