fix the Scripts not permitted to use method hudson.plugins.git.GitSCM getUserRemoteConfigs error

Jenkinsfile

@@ -1,20 +1,16 @@
 #!/usr/bin/env groovy
 import groovy.json.JsonOutput
 
-def gitRepo = ""
+def gitRepo = params.GIT_REPO
 def gitBranch = params.GIT_BRANCH != null && params.GIT_BRANCH != "" ? params.GIT_BRANCH : "master"
 
 node('nodejs') {
   // Get Source Code from SCM (Git) as configured in the Jenkins Project
   stage('Checkout Source') {
     // For Jenkinsfile from GIT
-    if (gitRepo == null || gitRepo == "") {
+    checkout scm
-      checkout scm
+    // for inline scripts
-      gitRepo = scm.getUserRemoteConfigs()[0].getUrl()
+    //git url: gitRepo, branch: gitBranch
-    } else {
-      // for inline scripts
-      git url: gitRepo, branch: gitBranch
-    }
   }
 
   def towerExtraVars = [