如何在Shell脚本中访问jenkins groovy变量的值以进行循环

当我传递在jenkins Groovy脚本中声明的变量的值时，其值未保留在远程服务器上运行的for循环中。奇怪的是，我能够在for循环之外访问相同的值。

这是我尝试使用的示例代码

#!/usr/bin/env groovy

def config
def COMMANDS_TO_CHECK='curl grep hello awk tr mkdir bc'
pipeline {

    agent {
        label "master"
    }

    stages {
            stage ('Validation of commands') {         
            steps {
                script {
                    sh """
                    #!/bin/bash
                    /usr/bin/sshpass -p passwrd ssh user@host << EOF
                    hostname

                      echo $COMMANDS_TO_CHECK ---> This is printed
                          for CURRENT_COMMAND in \$COMMANDS_TO_CHECK
                        do
                        echo ${CURRENT_COMMAND}  ---> Why This is not printed?
                        echo \${CURRENT_COMMAND} ----> Why This is not printed?
                        done
                        hostname
EOF
                        exit

"""

}
}
}
}
}

输出量