refactor: migrate pricing entities to DML models (#10335)

Fixes: FRMW-2810

## Breaking changes
There is only one breaking change

- The `min_quantity` and `max_quantity` properties are now consistently typed as numbers. Earlier, it was [typed as numbers](https://github.com/medusajs/medusa/blob/develop/integration-tests/http/__tests__/price-list/admin/price-list.spec.ts#L68-L69) in some API responses and as [string in others](https://github.com/medusajs/medusa/blob/develop/integration-tests/http/__tests__/price-list/admin/price-list.spec.ts#L186-L187). I did not go to the bottom of this inconsistency, but the tests reveals them.

Co-authored-by: Adrien de Peretti <25098370+adrien2p@users.noreply.github.com>

packages/modules/pricing/integration-tests/__fixtures__/price-set/index.ts

@@ -1,6 +1,7 @@
 import { CreatePriceSetDTO } from "@medusajs/framework/types"
 import { SqlEntityManager } from "@mikro-orm/postgresql"
 import { Price, PriceSet } from "@models"
+import { toMikroORMEntity } from "@medusajs/framework/utils"
 import { defaultPriceSetsData } from "./data"
 
 export * from "./data"
@@ -16,12 +17,15 @@ export async function createPriceSets(
     const prices = priceSetDataClone.prices || []
     delete priceSetDataClone.prices
 
-    let priceSet = manager.create(PriceSet, priceSetDataClone) as PriceSet
+    let priceSet = manager.create(
+      toMikroORMEntity(PriceSet),
+      priceSetDataClone
+    ) as PriceSet
 
     manager.persist(priceSet)
 
     for (let priceData of prices) {
-      const price = manager.create(Price, {
+      const price = manager.create(toMikroORMEntity(Price), {
         ...priceData,
         price_set_id: priceSet.id,
         title: "test",