Fix changeset description to properly describe the implemented features

Co-authored-by: mvantellingen <245297+mvantellingen@users.noreply.github.com>

Author: Copilot

.changeset/plain-gifts-cross.md

@@ -2,4 +2,4 @@
 "@labdigital/commercetools-mock": patch
 ---
 
-Remove discounted field mapping from priceFromDraft as it should be calculated
+Implement missing fields for priceFromDraft function: customerGroup, validFrom, validUntil, tiers, and custom fields