Add 'comment' github pull_request event action

Change-Id: I60aa77461cc4f5642ab3da14570f6e7ac3bead1a
Co-Authored-By: Jesse Keating <omgjlk@us.ibm.com>
diff --git a/tests/fixtures/layouts/basic-github.yaml b/tests/fixtures/layouts/basic-github.yaml
index f10fa6b..53f0c0f 100644
--- a/tests/fixtures/layouts/basic-github.yaml
+++ b/tests/fixtures/layouts/basic-github.yaml
@@ -8,6 +8,9 @@
             - opened
             - changed
             - reopened
+        - event: pull_request
+          action: comment
+          comment: 'test me'
     success:
       github: {}
     failure: