fix(dashboard, fulfilment): fulfilment providers enabled check (#9415)

**What**
- hide disabled fulfilment providers on the admin
- check if the fulfilment provider has an identifier when loading providers

---

FIXES CC-549

packages/modules/payment/src/loaders/providers.ts

@@ -6,6 +6,7 @@ import {
   ModulesSdkTypes,
 } from "@medusajs/framework/types"
 import { Lifetime, asFunction, asValue } from "awilix"
+import { MedusaError } from "@medusajs/utils"
 
 import { PaymentProviderService } from "@services"
 import * as providers from "../providers"
@@ -13,6 +14,13 @@ import * as providers from "../providers"
 const PROVIDER_REGISTRATION_KEY = "payment_providers"
 
 const registrationFn = async (klass, container, pluginOptions) => {
+  if (!klass?.PROVIDER) {
+    throw new MedusaError(
+      MedusaError.Types.INVALID_ARGUMENT,
+      `Trying to register a payment provider without a provider identifier.`
+    )
+  }
+
   const key = `pp_${klass.PROVIDER}_${pluginOptions.id}`
 
   container.register({