Update URL for GN quick start guide.

Change-Id: I8f332a42bd587fc7321a6a60838bcc39bbc0d5ea
diff --git a/docs/build-instructions.md b/docs/build-instructions.md
index 9ba085c..ec74c02 100644
--- a/docs/build-instructions.md
+++ b/docs/build-instructions.md
@@ -144,4 +144,4 @@
 Enables [Undefined Behavior Sanitizer](https://clang.llvm.org/docs/UndefinedBehaviorSanitizer.html)
 
 
-[gn-quickstart]: https://chromium.googlesource.com/chromium/src/+/master/tools/gn/docs/quick_start.md
+[gn-quickstart]: https://gn.googlesource.com/gn/+/master/docs/quick_start.md