ci: run complete-pr task on untrusted PRs (#659)

These PRs are lacking codecov, but that doesn't seem bad enough to
prevent running the `complete` task (which doesn't depend on codecov
anyway).

Author: jcristau

taskcluster/kinds/complete/kind.yml

@@ -15,7 +15,7 @@ kind-dependencies:
 tasks:
   pr:
     description: Ensures required PR tasks have completed
-    run-on-tasks-for: ["github-pull-request"]
+    run-on-tasks-for: ["github-pull-request", "github-pull-request-untrusted"]
     worker-type: succeed
     from-deps:
       group-by: all