Require internal recipe tryjob

BUG=628801

Review-Url: https://codereview.chromium.org/2187073004

infra/config/cq.cfg

@@ -23,5 +23,9 @@ verifiers {
       builders { name: "Depot Tools Presubmit" }
       builders { name: "Recipe Roll Downstream Tester" }
     }
+    buckets {
+      name: "master.internal.infra.try"
+      builders { name: "build-internal-recipe-downstream-tryjob" }
+    }
   }
 }