Fix broken link in CONTRIBUTING.md
Update link text and URL to point to current topic:
Contributing to Grid at to grid.hyperledger.org/community/contributing.html
@@ -16,6 +16,6 @@ contributors who can:
* Improve documentation
For more information, please see
-[Contributing](https://grid.hyperledger.org/community/contributing/)
+[Contributing to Grid](https://grid.hyperledger.org/community/contributing.html)
on the Hyperledger Grid website.
