Add updated cpe for vulnerability scanners

Bug: b/201572953
Change-Id: Ib83bc8fd2df3f1b840db28442092182348c1b7a0
diff --git a/METADATA b/METADATA
index fe7d3ed..24b198f 100644
--- a/METADATA
+++ b/METADATA
@@ -20,4 +20,7 @@
     month: 10
     day: 28
   }
+  security {
+      tag: "NVD-CPE2.3:cpe:/a:cups:cups:2.3.3"
+  }
 }