ci: delete the workspace tmp dir

Author: markoburcul

ci/Jenkinsfile.linux

@@ -175,6 +175,7 @@ pipeline {
         disableDeferredWipeout: true,
         deleteDirs: true
       )
+      dir("${env.WORKSPACE}@tmp") { deleteDir() }
     }
   }
 }

ci/Jenkinsfile.macos

@@ -159,6 +159,7 @@ pipeline {
         disableDeferredWipeout: true,
         deleteDirs: true
       )
+      dir("${env.WORKSPACE}@tmp") { deleteDir() }
     }
   }
 }