internal/gcp: add image to README

Change-Id: Iff91e89bd1dc5f293d980461bd8664cdaf4a715a
Reviewed-on: https://go-review.googlesource.com/c/oscar/+/608636
Reviewed-by: Tatiana Bradley <tatianabradley@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
diff --git a/internal/gcp/README.md b/internal/gcp/README.md
index 13d3307..56f845e 100644
--- a/internal/gcp/README.md
+++ b/internal/gcp/README.md
@@ -62,9 +62,10 @@
 
 Roll back a service from the UI:
 
-1. Click the service name (gaby-devel or gaby-prod) in Cloud Run.
+1. Click the service name (gaby-devel or gaby-prod) in [Cloud Run](https://console.cloud.google.com/run?project=oscar-go-1).
 2. Click the "REVISIONS" tab.
 3. For the revision you want to roll back, click the "Actions" nav bar, then "Manage Traffic":
+![select Manage Traffic](manage-traffic.png)
 4. Set the traffic for this revision to 0%, and pick a healthy revision (usually the previous one), to direct 100% of traffic to. Click "SAVE".
 
 Or from the command line:
diff --git a/internal/gcp/manage-traffic.png b/internal/gcp/manage-traffic.png
new file mode 100644
index 0000000..ba48caf
--- /dev/null
+++ b/internal/gcp/manage-traffic.png
Binary files differ