Unhardcode jenkins_secret key in reclass

Prod related: PROD-26352 (PROD:26352)

Change-Id: Ic6623d6fcf118e8410e55a4628fbe454a3f8efcc
diff --git a/docker/swarm/stack/jenkins/slave_base.yml b/docker/swarm/stack/jenkins/slave_base.yml
index 648a572..3af4cc3 100644
--- a/docker/swarm/stack/jenkins/slave_base.yml
+++ b/docker/swarm/stack/jenkins/slave_base.yml
@@ -4,7 +4,6 @@
   _param:
     jenkins_master_host: ${_param:control_vip_address}
     jenkins_master_port: 8081
-    jenkins_secret: "7c40abc1a7df2d26dd6b2e4421af17218df75a16fcbd5e3aa6017d9f47eaeabe"
     jenkins_master_url: http://${_param:jenkins_master_host}:${_param:jenkins_master_port}
     jenkins_slave_user: ${_param:jenkins_client_user}
     jenkins_slave_password: ${_param:jenkins_client_password}