Add defaults for HTTGetAction.Path & test actions

The comment says optional - this makes it optional.  Test handler actions.

pkg/api/v1beta3/defaults.go

@@ -85,5 +85,10 @@ func init() {
 				obj.Protocol = "TCP"
 			}
 		},
+		func(obj *HTTPGetAction) {
+			if obj.Path == "" {
+				obj.Path = "/"
+			}
+		},
 	)
 }