com.unity.xr.arfoundation 3.1.0-preview.3 Package Notes

Fix `HelpURL`s on `MonoBehaviour`s to point to the 3.1 version of the documentation.
Added `FormerlySerializedAs` to `ARAnchorManager.m_AnchorPrefab` field to preserve any prefab specified when it was the `ARReferencePointManager`.
Fixed issue that broke the camera background rendering when URP post-processing was enabled on the AR camera.
### New
Added support for HDR light estimation to ARCameraManager.
Added script updater support for facilitating the rename of Reference Points to Anchors

com.unity.xr.arfoundation 3.1.0-preview.3