Removed setup stage and now only run queue stage on delta branch.

Jenkinsfile

@@ -1,13 +1,6 @@
 pipeline {
     agent any
     stages {
-        stage('setup') {
-            steps {
-                sh 'git checkout delta'
-                sh 'git reset --hard origin/delta'
-                sh 'git clean -fd'
-            }
-        }
         stage('startup and shutdown check') {
             steps {
                 sh './testrun.sh'
@@ -16,6 +9,9 @@ pipeline {
             }
         }
         stage('queue') {
+            when {
+                branch '**/delta'
+            }
             steps {
                 checkout([$class: 'GitSCM', branches: [[name: '*/master']], extensions: [], userRemoteConfigs: [[credentialsId: '359ebf7c-e2b9-45ec-992c-ff8d5549deb6', url: 'git@dev.sys.reslate.xyz:ydeng/rsemcs.git']]])
                 sh 'git merge --strategy-option theirs origin/delta'