feat(core-flows,medusa,order): remove return shipping (#8137)

What:
* `DELETE /admin/returs/:id/shipping_methods/:action_id`

FIXES: CC-187

packages/modules/order/src/migrations/Migration20240715174100.ts

@@ -0,0 +1,20 @@
+import { Migration } from "@mikro-orm/migrations"
+
+export class Migration20240715102100 extends Migration {
+  async up(): Promise<void> {
+    const sql = `
+      DROP INDEX IF EXISTS "IDX_order_shipping_method_shipping_option_id";
+
+      ALTER TABLE "order_shipping_method"
+        ADD COLUMN if NOT exists "deleted_at" timestamptz NULL;
+
+      CREATE INDEX IF NOT EXISTS "IDX_order_shipping_method_shipping_option_id" ON "order_shipping_method" (
+          shipping_option_id
+      ) WHERE deleted_at IS NULL;
+
+      
+    `
+
+    this.addSql(sql)
+  }
+}