Handle case where returned object from a Watch is not a Pod (#132)

* Handle cases where returned object from a watch is not a Pod

Author: harjsing7

testing/it_sidecar/stern/watch.go

@@ -59,7 +59,13 @@ func Watch(ctx context.Context, i v1.PodInterface, podFilter *regexp.Regexp, con
 					return
 				}
 
-				pod := e.Object.(*corev1.Pod)
+				var (
+					pod *corev1.Pod
+					ok  bool
+				)
+				if pod, ok = e.Object.(*corev1.Pod); !ok {
+					continue
+				}
 
 				if !podFilter.MatchString(pod.Name) {
 					continue