Update trigger for docker image build & mirrors

Change-Id: I49a89143b21d3521f07d77f828b9632fa0fa5254
diff --git a/jenkins/client/job/git-mirrors/upstream/init.yml b/jenkins/client/job/git-mirrors/upstream/init.yml
index e11e63c..cc267d9 100644
--- a/jenkins/client/job/git-mirrors/upstream/init.yml
+++ b/jenkins/client/job/git-mirrors/upstream/init.yml
@@ -25,7 +25,8 @@
                 project:
                   "{{downstream}}":
                     branches:
-                      - master
+                      - compare_type: "REG_EXP"
+                        name: "(.*?)"
                 message:
                   build_successful: "Build successful"
                   build_unstable: "Build unstable"