message: reuse discoveryServiceRef
diff: @@ -18,7 +18,7 @@ import { PluginEndpointDiscovery } from '@backstage/backend-common';
  import {
  createBackendModule,
  createServiceFactory,
  - createServiceRef,
  + discoveryServiceRef,
  } from '@backstage/backend-plugin-api';
  import { startTestBackend } from '@backstage/backend-test-utils';
  import { CatalogClient } from '@backstage/catalog-client';
  @@ -27,9 +27,7 @@ import { catalogServiceRef } from './catalogService';
  describe('catalogServiceRef', () => {
  it('should return a catalogClient', async () => {
  const mockDiscoveryFactory = createServiceFactory({
  - service: createServiceRef<PluginEndpointDiscovery>({
  - id: 'core.discovery',
  - }),
  + service: discoveryServiceRef,
  deps: {},
  factory: async ({}) => {
  return async () => jest.fn() as unknown as PluginEndpointDiscovery;
  