Add what's new entry

dist/preview release/what's new.md

@@ -63,6 +63,9 @@
 - Added `ShaderMaterial.setColor4Array` ([JonathanTron](https://github.com/JonathanTron/))
 - Added `ShaderMaterial.setArray4` ([JonathanTron](https://github.com/JonathanTron/))
 
+### Documentation
+- Added a note on shallow bounding of getBoundingInfo ([tibotiber](https://github.com/tibotiber))
+
 ## Bug fixes
 - Added support for `AnimationGroup` serialization ([Drigax](https://github.com/drigax/))
 - Removing assetContainer from scene will also remove gui layers ([TrevorDev](https://github.com/TrevorDev))