The following cloud formation will sets up an aws amplify app.

  AmplifyApp:
    Type: AWS::Amplify::App
    Properties:
      Name: name-of-app

  AmplifyBranch:
    Type: AWS::Amplify::Branch
    Properties:
      AppId: !GetAtt AmplifyApp.AppId
      BranchName: dev

What cloud formation would I use to activate the "Deploy Update flow" within the amplify app and connect it to an already existing S3 bucket for web content?