doc: use new Gerrit link and link to our instance of it
Change-Id: Ic07f9e5d9d37affbd6e4ffee5e1df8c807402f7b
Reviewed-on: https://go-review.googlesource.com/20463
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
index ff54c47..64f91fd 100644
--- a/CONTRIBUTING.md
+++ b/CONTRIBUTING.md
@@ -1,7 +1,8 @@
# Contributing to godoc.org
**We do not accept GitHub pull requests**
-(we use [Gerrit](https://code.google.com/p/gerrit/) instead for code review).
+(we use [an instance](https://go-review.googlesource.com/) of the
+[Gerrit](https://www.gerritcodereview.com/) code review system instead).
To get started contributing to this project,
clone the repository from its canonical location
