refactor: remove duplicate remixProject export

The remixProject reducer is already being exported from the
`src/exported-reducers.ts` file which makes this export redundant.

Author: sebjacobs

packages/scratch-gui/src/index.ts

@@ -4,7 +4,6 @@ import {legacyConfig} from './legacy-config';
 export {default} from './containers/gui.jsx';
 export {default as GUIComponent} from './components/gui/gui.jsx';
 export {default as AppStateHOC} from './lib/app-state-hoc.jsx';
-export {remixProject} from './reducers/project-state.js';
 export {setAppElement} from 'react-modal';
 
 export {legacyConfig};