Fix broken CONTRIBUTING.md link in readme

Author: fnlctrl

README.md

@@ -42,7 +42,7 @@ For questions and support please use the [Gitter chat room](https://gitter.im/vu
 
 ## Issues
 
-Please make sure to read the [Issue Reporting Checklist](https://github.com/vuejs/vue/blob/dev/CONTRIBUTING.md#issue-reporting-guidelines) before opening an issue. Issues not conforming to the guidelines may be closed immediately.
+Please make sure to read the [Issue Reporting Checklist](https://github.com/vuejs/vue/blob/dev/.github/CONTRIBUTING.md#issue-reporting-guidelines) before opening an issue. Issues not conforming to the guidelines may be closed immediately.
 
 ## Contribution