update release notes

Author: andy-bridger

docs/source/release/v6.13.0/Diffraction/Engineering/New_features/38863.rst

@@ -1,2 +1,4 @@
 - Renamed `Crop Calibration` within the `Engineering Diffraction` calibration interface to `Set Calibration Region of Interest` to more accurately reflect its functionality.
 - Renamed `Custom CalFile` to `Custom Grouping File` and allowed the provided file to be `.xml` as well as `.cal`. This brings it inline with the current detector grouping IO algorithms, :ref:`SaveDetectorsGrouping <algm-SaveDetectorsGrouping-v1>` and :ref:`LoadDetectorsGroupingFile <algm-LoadDetectorsGroupingFile-v1>`.
+- Changed the naming suffix for custom file example_group.xml from _Custom to _Custom_example_group so they don't get overwritten when custom grouping is changed (also more clear to the user what grouping is being used).
+- Changed it so the vanadium normalisation is always rerun for GROUP.CUSTOM and GROUP.CROPPED