updated dockerfile

Jenkinsfile

@@ -6,7 +6,7 @@ pipeline {
             steps {
                 script {
                     def imageName = "python-jenkins-project:${BUILD_NUMBER}"
-                    docker.build(imageName, '.')
+                    sh "DOCKER_BUILDKIT=0 docker build --no-cache -t ${imageName} ."
                     env.IMAGE_NAME = imageName
                 }
             }