change Jenkinsfile

Jenkinsfile

@@ -2,7 +2,7 @@ node('haimaxy-jnlp') {
     stage('Clone') {
       echo "1.Clone Stage"
       // git url: "https://github.com/cnych/jenkins-demo.git"
-      // checkout scm
+      checkout scm
       script {
         build_tag = sh(returnStdout: true, script: 'git rev-parse --short HEAD').trim()