Added note for AWSAppSyncClient

[Skaronator]

I had some trouble to get server side rendering with the AWSAppSyncClient working. I finally found a solution in awslabs/aws-mobile-appsync-sdk-js#82 but it might be worth to share it here as well. Instead of adding a big code block to each file I'll just refer to this Pull Request.

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In case you want to use the AWSAppSyncClient you just need to replace the create() function with this function:

import AWSAppSyncClient from 'aws-appsync';
import { AUTH_TYPE } from 'aws-appsync/lib/link/auth-link';

function create(initialState) {
  const client = new AWSAppSyncClient({
    url: AWS_AppSync.graphqlEndpoint,
    region: AWS_AppSync.region,
    auth: {
      type: AUTH_TYPE.API_KEY,
      apiKey: AWS_AppSync.apiKey,

      // Amazon Cognito Federated Identities using AWS Amplify
      //credentials: () => Auth.currentCredentials(),

      // Amazon Cognito user pools using AWS Amplify
      // type: AUTH_TYPE.AMAZON_COGNITO_USER_POOLS,
      // jwtToken: async () => (await Auth.currentSession()).getIdToken().getJwtToken(),
    },
    disableOffline: true,
  }, {
    cache: new InMemoryCache().restore(initialState || {}),
    ssrMode: true
  });

  return client;
}