Remove isStarted prop from GreenFlagOverlay

Since scratchfoundation#3885, the GreenFlagOverlay has been hidden by the Stage component
instead of having to hide itself if the project has been started. Thus
there's no need for GreenFlagOverlay to know whether the project has
been started.

Author: adroitwhiz

src/containers/green-flag-overlay.jsx

@@ -21,8 +21,6 @@ class GreenFlagOverlay extends React.Component {
     }
 
     render () {
-        if (this.props.isStarted) return null;
-
         return (
             <Box
                 className={this.props.wrapperClass}
@@ -42,13 +40,11 @@ class GreenFlagOverlay extends React.Component {
 
 GreenFlagOverlay.propTypes = {
     className: PropTypes.string,
-    isStarted: PropTypes.bool,
     vm: PropTypes.instanceOf(VM),
     wrapperClass: PropTypes.string
 };
 
 const mapStateToProps = state => ({
-    isStarted: state.scratchGui.vmStatus.started,
     vm: state.scratchGui.vm
 });