Chore: Update global-jjb

Fetch latest fixes from global-jjb
Add default branch value which is mainly required by the releases
jobs.

Change-Id: Id4caa42ecd2fde385ffe0abbf6bde1d809a09c03
Signed-off-by: Jessica Wagantall <jwagantall@linuxfoundation.org>
diff --git a/global-jjb b/global-jjb
index 76aaece..f4b5443 160000
--- a/global-jjb
+++ b/global-jjb
@@ -1 +1 @@
-Subproject commit 76aaece53118efec0bdcd003efb31f03d6286c92
+Subproject commit f4b544362ab8764479ce7a4b087c67e923500963
diff --git a/jjb/defaults.yaml b/jjb/defaults.yaml
index d401488..ebda548 100644
--- a/jjb/defaults.yaml
+++ b/jjb/defaults.yaml
@@ -26,6 +26,9 @@
     # counter-intuitively, the quotes here are REQUIRED
     container-push-registry: "{container-staging-registry}"
 
+    # Default branch
+    branch: master
+
     # Don't define default java version here,
     # it will not be used by lf-maven-jobs.
     # Default maven version