Implement metamask installation flow

packages/website/ts/components/onboarding/onboarding_flow.tsx

@@ -17,9 +17,16 @@ const joyrideStyleOptions: StyleOptions = {
 
 // Wrapper around Joyride with defaults and styles set
 export class OnboardingFlow extends React.Component<OnboardingFlowProps> {
+    private _joyrideRef: React.RefObject<Joyride>;
+    constructor(props: OnboardingFlowProps) {
+        super(props);
+        this._joyrideRef = React.createRef();
+    }
+
     public render(): React.ReactNode {
         return (
             <Joyride
+                ref={this._joyrideRef}
                 run={this.props.isRunning}
                 debug={true}
                 steps={this.props.steps}