Adding executor node param to BBR Pipeline

Change-Id: I224be2c627e69448af9a0371a23da17fcda56003
diff --git a/jjb/bbr.yaml b/jjb/bbr.yaml
index 8c3ca31..3324f33 100644
--- a/jjb/bbr.yaml
+++ b/jjb/bbr.yaml
@@ -40,3 +40,8 @@
       - timed: |
           TZ=America/Los_Angeles
           H * * * *
+    parameters:
+      - string:
+          name: executorNode
+          default: 'ubuntu16.04-basebuild-1c-2g'
+          description: 'Name of the Jenkins node to run the job on'