Make stepler container build from 'pike' branch

Change-Id: I1749818378046b1ebdd7a728cd3fe7d9ac0cb6da
Related-prod: PROD-20774
diff --git a/jenkins/client/job/oscore/qa.yml b/jenkins/client/job/oscore/qa.yml
index 6d54082..13d0e76 100644
--- a/jenkins/client/job/oscore/qa.yml
+++ b/jenkins/client/job/oscore/qa.yml
@@ -25,6 +25,7 @@
                   mcp/{{oscore-qa-project}}:
                     branches:
                       - master
+                      - pike
                 event:
                   change:
                     - merged
@@ -43,7 +44,7 @@
                 default: "mirantis/oscore/{{oscore-qa-project}}"
               IMAGE_TAG:
                 type: string
-                default: "latest"
+                default: ""
               DOCKER_REGISTRY:
                 type: string
                 default: "docker-prod-local.docker.mirantis.net"