fix: infer MA currency on PL create (#2232)

**What**
- a MoneyAmount record can be created with either providing region or currency. MA records cannot be inserted in the DB without currency due to not null constraints therefore the currency needs to be inferred from provided region

**How**
- by using the same utility that fixes this issue on PL update

**Testing**
- extend the "create PL" integration test to handle a MA with a region

---

FIXES CORE-525

packages/medusa/src/services/__tests__/price-list.js

@@ -44,6 +44,7 @@ describe("PriceListService", () => {
     priceListRepository,
     moneyAmountRepository,
     featureFlagRouter: new FlagRouter({}),
+    regionService: RegionServiceMock,
   })
 
   beforeEach(async () => {
@@ -129,7 +130,8 @@ describe("PriceListService", () => {
     updateRelatedMoneyAmountRepository.save = jest
       .fn()
       .mockImplementation(() => Promise.resolve())
-    updateRelatedMoneyAmountRepository.updatePriceListPrices = new MoneyAmountRepository().updatePriceListPrices
+    updateRelatedMoneyAmountRepository.updatePriceListPrices =
+      new MoneyAmountRepository().updatePriceListPrices
 
     const updateRelatedPriceListService = new PriceListService({
       manager: MockManager,

packages/medusa/src/services/price-list.ts

@@ -140,7 +140,8 @@ class PriceListService extends TransactionBaseService {
         const priceList = await priceListRepo.save(entity)
 
         if (prices) {
-          await moneyAmountRepo.addPriceListPrices(priceList.id, prices)
+          const prices_ = await this.addCurrencyFromRegion(prices)
+          await moneyAmountRepo.addPriceListPrices(priceList.id, prices_)
         }
 
         if (customer_groups) {
@@ -507,7 +508,9 @@ class PriceListService extends TransactionBaseService {
     const prices_: typeof prices = []
 
     const regionServiceTx = this.regionService_.withTransaction(this.manager_)
-    for (const p of prices) {
+    for (const price of prices) {
+      const p = { ...price }
+
       if (p.region_id) {
         const region = await regionServiceTx.retrieve(p.region_id)