test(storybook): Add Wrapper component for ThemeProvider

.storybook/preview.tsx

@@ -0,0 +1,5 @@
+import React from 'react'
+import { addDecorator } from '@storybook/react'
+import { Wrapper } from './wrapper'
+
+addDecorator(storyFn => <Wrapper>{ storyFn() }</Wrapper>)

.storybook/wrapper.tsx

@@ -0,0 +1,11 @@
+import React from 'react'
+import { ThemeProvider } from 'styled-components'
+import { lightTheme } from '@/styles/theme'
+
+export const Wrapper: React.FC = ({ children }) => {
+  return (
+    <ThemeProvider theme={ lightTheme }>
+      { children }
+    </ThemeProvider>
+  )
+}

components/atoms/time_svg/index.stories.tsx

@@ -1,14 +1,9 @@
 import React from 'react'
-import { ThemeProvider } from 'styled-components'
-import { lightTheme } from '@/styles/theme'
 import { TimeSvg } from '.'
 
 export default {
   title: 'components/atoms/time_svg/index',
   component: TimeSvg
 }
 
-export const Default = () =>
-  <ThemeProvider theme={ lightTheme }>
-    <TimeSvg date="2020-07-26" className="foo" />
-  </ThemeProvider>
+export const Default = () => <TimeSvg date="2020-07-26" className="foo" />