chore(order): simplify order engine (#8188)

what:
- remove unused features of order changes calculation engine

packages/modules/order/src/utils/set-action-reference.ts

@@ -4,9 +4,3 @@ export function setActionReference(existing, action, options) {
     existing.actions.push(action)
   }
 }
-
-export function unsetActionReference(existing, action) {
-  if (Array.isArray(existing?.actions)) {
-    existing.actions = existing.actions.filter((a) => a.id !== action.id)
-  }
-}