docs: fix broken link to "Contribute" on README.md (#1954)

Author: talkor

README.md

@@ -85,7 +85,7 @@ If you have a VuePress-related project/component/tool, add it with a pull reques
 
 ### Code Contributors
 
-This project exists thanks to all the people who contribute. [[Contribute](CONTRIBUTING.md)].
+This project exists thanks to all the people who contribute. [[Contribute](.github/CONTRIBUTING.md)].
 <a href="https://github.com/vuejs/vuepress/graphs/contributors"><img src="https://opencollective.com/vuepress/contributors.svg?width=890&button=false" /></a>
 
 ### Financial Contributors