サイド・バーの幅を可変に (#385) (#396)

Reviewed-on: http://git.miteruzo.com/miteruzo/btrc-hub/pulls/396
Co-authored-by: miteruzo <miteruzo@naver.com>
Co-committed-by: miteruzo <miteruzo@naver.com>

frontend/src/pages/materials/MaterialBasePage.tsx

@@ -6,9 +6,11 @@ import type { FC } from 'react'
 
 
 const MaterialBasePage: FC = () => (
-    <div className="md:flex md:flex-1 overflow-y-auto md:overflow-y-hidden">
+    <div
+	data-sidebar-container
+	className="md:flex md:flex-1 overflow-y-auto md:overflow-y-hidden">
       <MaterialSidebar/>
       <Outlet/>
     </div>)
 
-export default MaterialBasePage
+export default MaterialBasePage