message: docs: add AngularConnect announcement for after ng-conf
  PR Close
diff: "linkUrl": "https://angularmix.com/"
  },
  {
  - "startDate": "2018-08-15",
  - "endDate": "2018-11-06",
  - "message": "Join us for Angular Connect<br/>November 6th-7th, 2018",
  + "startDate": "2019-05-03",
  + "endDate": "2019-09-18",
  + "message": "Join us for Angular Connect<br/>September 19th-20th, 2019",
  "imageUrl": "generated/images/marketing/home/angular-connect.png",
  - "linkUrl": "https://angularconnect.com/"
  + "linkUrl": "https://www.angularconnect.com/?utm_source=angular.io&utm_medium=referral"
  }
  ]
  