为什么在SCM中没有更改却触发了管道作业

Question

我正在为我的项目设置管道作业，我想做的是设置该作业，每隔两分钟ping通SCM，以检查是否有更改，如果是，则使用管道脚本来构建作业。

这是我的管道作业配置：

和管道脚本：

pipeline {
    agent any 
    options { 
        disableConcurrentBuilds() 
    } 
    tools {
        maven 'Maven 3.6'
    }
    stages {
        stage('Git Checkout') {
            steps {
                sh 'echo "Git Checkout"'
                checkout([$class: 'GitSCM', branches: [[name: 'master']], doGenerateSubmoduleConfigurations: false, extensions: [], submoduleCfg: [], userRemoteConfigs: [[credentialsId: 'my-credential', url: 'my-git-url']]])
            }
        }
        stage('Maven Build') {
            steps {
                sh 'mvn clean deploy -s $WORKSPACE/custom-config/settings.xml -Dsettings.security=$WORKSPACE/custom-config/settings-security.xml'
            }
        }
        stage('Maven Build and SonarQube Analysis') {
            steps {
                withSonarQubeEnv('Sonar Qube') {
                    sh 'mvn sonar:sonar -Dsonar.projectKey=com.product:backend'
                }
            }
        }
        stage('SonarQube Quality Gate') {
            steps {
                timeout(time: 10, unit: 'MINUTES') {
                    waitForQualityGate abortPipeline: true
                }
            }
        }
    }
    post {
        failure {
            mail bcc: '', body: "See ${env.BUILD_URL}", cc: '', charset: 'UTF-8', from: '', mimeType: 'text/html', replyTo: '', subject: "Build failed in Jenkins: ${env.JOB_NAME} #${env.BUILD_NUMBER}", to: "my.email@gmail.com";
        }
        unstable {
            mail bcc: '', body: "See ${env.BUILD_URL}", cc: '', charset: 'UTF-8', from: '', mimeType: 'text/html', replyTo: '', subject: "Build unstable in Jenkins: ${env.JOB_NAME} #${env.BUILD_NUMBER}", to: "my.email@gmail.com";
        }
    }
}

一切正常，除了每两分钟触发一次作业，尽管我在脚本中设置的master分支没有任何变化。有人可以在这里帮助我防止此操作。我希望仅在SCM发生变化时才触发作业。非常感谢你！