print jenkins enviroment variables

ci/jenkins/Jenkinsfile

@@ -77,6 +77,7 @@ pipeline {
                                         steps {
                                             container("milvus-${BINARY_VERSION}-build-env") {
                                                 script {
+                                                    sh 'printenv'
                                                     load "${env.WORKSPACE}/ci/jenkins/step/build.groovy"
                                                 }
                                             }