fix: DML relation management for many to one relation ship foreign keys (#7790)

FIXES CORE-2369

cc @thetutlage 

Co-authored-by: Oli Juhl <59018053+olivermrbl@users.noreply.github.com>

packages/modules/fulfillment/mikro-orm.config.dev.ts

@@ -1,12 +1,7 @@
 import * as entities from "./src/models"
-import { TSMigrationGenerator } from "@medusajs/utils"
+import { defineMikroOrmCliConfig } from "@medusajs/utils"
 
-module.exports = {
+module.exports = defineMikroOrmCliConfig({
   entities: Object.values(entities),
-  schema: "public",
-  clientUrl: "postgres://postgres@localhost/medusa-fulfillment",
-  type: "postgresql",
-  migrations: {
-    generator: TSMigrationGenerator,
-  },
-}
+  databaseName: "medusa-fulfillment",
+})