add reset_all and undo buttons to error boundary. no styling

sites/shared/components/error/reset-buttons.js

@@ -0,0 +1,10 @@
+import { useTranslation } from 'next-i18next'
+
+export default function ({resetGist, undoGist}) {
+	const {t} = useTranslation(['app'])
+
+	return (<>
+	<button className="btn btn-primary" onClick={undoGist}>{t('undo')}</button>
+	<button className="btn btn-primary" onClick={resetGist}>{t('reset_all')}</button>
+	</>
+)}