title: JenkinsFile Clean Workspace not working in post function
body: <p>Hi I am not able to clean the workspace with below Jenkinsfile its throwing below error please suggest, have tried delete directory Also it is also not working.</p>
  
  <p>jenkins 2.162 version</p>
  
  <pre><code>Error :
  Error when executing always post condition:
  hudson.AbortException: script returned exit code 255
      at org.jenkinsci.plugins.workflow.steps.durable_task.DurableTaskStep$Execution.handleExit(DurableTaskStep.java:569)
      at org.jenkinsci.plugins.workflow.steps.durable_task.DurableTaskStep$Execution.check(DurableTaskStep.java:515)
      at org.jenkinsci.plugins.workflow.steps.durable_task.DurableTaskStep$Execution.run(DurableTaskStep.java:461)
      at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511)
      at java.util.concurrent.FutureTask.run(FutureTask.java:266)
      at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.access$201(ScheduledThreadPoolExecutor.java:180)
      at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.run(ScheduledThreadPoolExecutor.java:293)
      at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
      at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
      at java.lang.Thread.run(Thread.java:748)
  </code></pre>
  
  <hr>
  
  <pre><code>pipeline 
  {
  agent any
  }
  tools {maven "maven3"}
  stages 
  {
  stage("Build") 
  {
  steps 
  {
  sshagent(['bitbucketssh']) 
  {
  script 
  {
  sh "bash ./ciBuild.sh"
  }
  }
  }
  }
  }
  post 
  {
  always 
  {
  cucumber buildStatus: 'UNSTABLE',
  failedFeaturesNumber: 1,
  failedScenariosNumber: 1,
  skippedStepsNumber: 1,
  failedStepsNumber: 1,
  sshagent(['bitbucketssh']) 
  {
  script 
  {
  sh "bash ./destroy.sh"
  cleanWs()       /* clean workspace now working 
  }
  }
  }
  }
  }
  </code></pre>