Update CHANGES.md

Author: shehzan10

CHANGES.md

@@ -20,6 +20,7 @@ Change Log
 * Added a [new Sandcastle example](https://cesiumjs.org/Cesium/Build/Apps/Sandcastle/?src=Time%20Dynamic%20Wheels.html) on using `nodeTransformations` to rotate a model's wheels based on its velocity. [#7361](https://github.com/AnalyticalGraphicsInc/cesium/pull/7361)
 * Added `EllipsoidRhumbLine` class as a rhumb line counterpart to `EllipsoidGeodesic`. [#7484](https://github.com/AnalyticalGraphicsInc/cesium/pull/7484)
 * Added rhumb line support to `PolygonGeometry`, `PolygonOutlineGeometry`, `PolylineGeometry`, `GroundPolylineGeometry`, and `SimplePolylineGeometry`. [#7492](https://github.com/AnalyticalGraphicsInc/cesium/pull/7492)
+* Improved the performance of `QuantizedMeshTerrainData.interpolateHeight`.  [#7508](https://github.com/AnalyticalGraphicsInc/cesium/pull/7508)
 
 ##### Fixes :wrench:
 * Fixed 3D Tiles performance regression. [#7482](https://github.com/AnalyticalGraphicsInc/cesium/pull/7482)