feat(medusa): invalidate price selection caching within update request (#3553)

* feat: invalidate price selection caching on update

* feat: add `onVariantsPricesUpdate` to PriceSelectionStrategy

* fix: update units

* fix: import

* Create .changeset/tame-pillows-heal.md

* fix: address feedback

* refactor: make `onVariantsPricesUpdate` optional

---------

Co-authored-by: fPolic <frane@medusajs.com>
Co-authored-by: Oliver Windall Juhl <59018053+olivermrbl@users.noreply.github.com>

packages/medusa/src/subscribers/pricing.ts

@@ -1,30 +0,0 @@
-import { ICacheService } from "@medusajs/types"
-import { EventBusService, ProductVariantService } from "../services"
-
-type ProductVariantUpdatedEventData = {
-  id: string
-  product_id: string
-  fields: string[]
-}
-
-class PricingSubscriber {
-  protected readonly eventBus_: EventBusService
-  protected readonly cacheService_: ICacheService
-
-  constructor({ eventBusService, cacheService }) {
-    this.eventBus_ = eventBusService
-    this.cacheService_ = cacheService
-
-    this.eventBus_.subscribe(
-      ProductVariantService.Events.UPDATED,
-      async (data) => {
-        const { id, fields } = data as ProductVariantUpdatedEventData
-        if (fields.includes("prices")) {
-          await this.cacheService_.invalidate(`ps:${id}:*`)
-        }
-      }
-    )
-  }
-}
-
-export default PricingSubscriber