change default branch for telegraf job

Change-Id: I160d34691fbc2493a8c7c7c0bd23c08a922d0f4a
diff --git a/jenkins/client/job/debian/packages/extra.yml b/jenkins/client/job/debian/packages/extra.yml
index 7d20688..298452e 100644
--- a/jenkins/client/job/debian/packages/extra.yml
+++ b/jenkins/client/job/debian/packages/extra.yml
@@ -132,11 +132,11 @@
             - package: telegraf
               dist: trusty
               build: telegraf
-              branch: master
+              branch: release-1.2
             - package: telegraf
               dist: xenial
               build: telegraf
-              branch: master
+              branch: release-1.2
           template:
             type: workflow-scm
             concurrent: false