Add CssBaseline decorator and Roboto to Storybook

.storybook/react/preview.js

@@ -1,6 +1,11 @@
 // License: LGPL-3.0-or-later
 import intlDecorate from '../../app/javascript/components/tests/intl';
+import cssBaseline from '../../app/javascript/components/tests/decorators/baseline'
+import '../../app/javascript/components/tests/decorators/roboto'
+
 const jest = require('jest-mock');
 window.jest = jest;
 
-export const decorators = [intlDecorate()]
+
+
+export const decorators = [intlDecorate(), cssBaseline()]

app/javascript/components/tests/decorators/baseline.tsx

@@ -0,0 +1,16 @@
+import React from 'react';
+import CssBaseline from '@material-ui/core/CssBaseline';
+import type {DecoratorFn} from '@storybook/react';
+import { StoryFn } from '@storybook/addons';
+
+
+function decorator(story:StoryFn<JSX.Element>): JSX.Element {
+	return (<>
+		<CssBaseline/>
+		{story()}
+	</>);
+}
+
+export default function decorate(): DecoratorFn {
+	return decorator;
+}

app/javascript/components/tests/decorators/roboto.ts

@@ -0,0 +1 @@
+import 'fontsource-roboto';