docs: Update Resources links in README (#5119)

* docs: Fix broken changelog link

* docs: Fix rest of links in Resources

* docs: Undo change

Co-authored-by: Jay <jasonsaayman@gmail.com>

README.md

@@ -1287,11 +1287,11 @@ You can use Gitpod, an online IDE(which is free for Open Source) for contributin
 
 ## Resources
 
-* [Changelog](https://github.com/axios/axios/blob/master/CHANGELOG.md)
-* [Upgrade Guide](https://github.com/axios/axios/blob/master/UPGRADE_GUIDE.md)
-* [Ecosystem](https://github.com/axios/axios/blob/master/ECOSYSTEM.md)
-* [Contributing Guide](https://github.com/axios/axios/blob/master/CONTRIBUTING.md)
-* [Code of Conduct](https://github.com/axios/axios/blob/master/CODE_OF_CONDUCT.md)
+* [Changelog](https://github.com/axios/CHANGELOG.md)
+* [Upgrade Guide](https://github.com/axios/UPGRADE_GUIDE.md)
+* [Ecosystem](https://github.com/axios/ECOSYSTEM.md)
+* [Contributing Guide](https://github.com/axios/CONTRIBUTING.md)
+* [Code of Conduct](https://github.com/axios/CODE_OF_CONDUCT.md)
 
 ## Credits