Change trigger on OnPrChanged test workflow

Author: gtjoseph

Diff for: .github/workflows/OnPRChanged.yml

@@ -1,23 +1,11 @@
-#
-# Workflows, like this one, that are triggered by PRs submitted
-# from forked repositories are severly limited in what they can do
-# for security reasons. For instance, they can't add or remove
-# labels or comments even on the PR that triggered them.  Since
-# we need to both of those things, GitHub recommends creating a
-# separate workflow that does those tasks that's triggered when
-# this PR workflow starts or finishes. Since that workflow isn't
-# being run in the context of a forked repo, it has all the
-# privileges needed to add and remove labels and comments.  The
-# accompanying OnPRStateChangedPriv workflow does just that.
-
 name: PRLabeled
 # WARNING!  The run name MUST start with "PR <pr_number>".
 # The accompanying privleged workflow parses this to find
 # the PR number.  It's the only reliable way it can get it.
 run-name: "PR ${{ github.event.number }} Labeled by ${{ github.actor }}"
 on:
-  pull_request:
-    types: [ opened,synchronize ]
+  pull_request_target:
+    types: [ opened,synchronize,labeled ]
 
 jobs:
   TestCalled: