TBR: mojo.discovery: update 'docs' references to point to vanadium.github.io

MultiPart: 10/27

Change-Id: I91261dea94860495f7a4db4d2ae5c9d3920bf91e
diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
index 69f169c..de03ce0 100644
--- a/CONTRIBUTING.md
+++ b/CONTRIBUTING.md
@@ -13,8 +13,8 @@
 ## Contributing code
 
 Please read the [contribution
-guidelines](https://github.com/vanadium/docs/blob/master/contributing/README.md)
-before sending patches.
+guidelines](https://vanadium.github.io/community/contributing.html) before
+sending patches.
 
 **We do not accept GitHub pull requests.** (We use
 [Gerrit](https://www.gerritcodereview.com/) instead for code reviews.)