[k8s-checker] Fix overwriting bug

Change-Id: I8d95672e727fe024415919dde5a012bdd8fa267d
Reviewed-on: https://skia-review.googlesource.com/c/buildbot/+/558636
Commit-Queue: Eric Boren <borenet@google.com>
Reviewed-by: Ravi Mistry <rmistry@google.com>
Commit-Queue: Ravi Mistry <rmistry@google.com>
Auto-Submit: Eric Boren <borenet@google.com>
diff --git a/k8s-checker/go/k8s-checker/main.go b/k8s-checker/go/k8s-checker/main.go
index 1e1bcad..131e319 100644
--- a/k8s-checker/go/k8s-checker/main.go
+++ b/k8s-checker/go/k8s-checker/main.go
@@ -341,11 +341,11 @@
 			containers = append(containers, config.Spec.Template.Spec.Containers)
 		}
 		for idx, app := range apps {
+			checkedInAppsToContainers[app] = util.StringSet{}
 			for _, c := range containers[idx] {
 				namespace := namespaces[idx]
 				liveAppContainerToImages := liveAppContainerToImagesByNamespace[namespace]
 
-				checkedInAppsToContainers[app] = util.StringSet{}
 				container := c.Name
 				committedImage := c.Image
 				checkedInAppsToContainers[app][c.Name] = true