change react-router to react-router-dom

When react-router-dom is treated as an external dependency in webpack config, an error will be caused:
` You should not use the < the Route > or withRouter () outside a < the Router > `

core/docz/src/utils/ScrollToTop.tsx

@@ -1,5 +1,5 @@
 import { ReactNode, Component } from 'react'
-import { withRouter, RouteComponentProps } from 'react-router'
+import { withRouter, RouteComponentProps } from 'react-router-dom'
 
 type ScrollToTopProps = RouteComponentProps<any>