message: fix test in `createFetcher`
diff: @@ -97,7 +97,7 @@ describe('getWsFetcher', () => {
  subscriptionUrl: 'wss://example',
  });
  expect(createClient.mock.calls[0]).toEqual([
  - { connectionParams: undefined, url: 'wss://example' },
  + { connectionParams: {}, url: 'wss://example' },
  ]);
  expect(SubscriptionClient.mock.calls).toHaveLength(0);
  });
  