jenkinsfile: stages is not recognized

Change-Id: I124df97bff609d897d617bf2fd9f4c5d1b81f5a8

extras/ci/client-qt-gnulinux/Jenkinsfile

@@ -95,7 +95,6 @@ pipeline {
 
                     docker.image('client-validation').withRun('-t -u '+jenkinsUser+' -v '+pwd()+':/foo:rw -w /foo -e BATCH_MODE=1', '/bin/bash') {
                         container -> code:{
-                            stages {
                             stage('Build Client') {
                                 steps {
                                     script {
@@ -149,4 +148,3 @@ pipeline {
         }
     }
 }
-}