docs: fix godoc README link
@@ -77,7 +77,7 @@ Google API | Status | Package
> **Stable status**: the API is mature and ready for production use. We will
> continue addressing bugs and feature requests.
-Documentation and examples are available at [godoc.org/cloud.google.com/go](godoc.org/cloud.google.com/go)
+Documentation and examples are available at [godoc.org/cloud.google.com/go](https://godoc.org/cloud.google.com/go)
## Go Versions Supported
