React refs is being deprecated. Consider changing it to **createRef** API.

[raamb]

this.refs is being deprecated. You might consider changing it to createRef API.

class MyComponent extends React.Component {
  constructor(props) {
    super(props);
    this.myRef = React.createRef();
  }
  render() {
    return <div ref={this.myRef} />;
  }
}

Originally posted by @Vivek205 in https://github.com/singnet/snet-dapp/pull/240/files