runTask: Correct quoting on post tasks

vars/runTask.groovy

@@ -76,8 +76,8 @@ def call(String task, String branch, String repo, String phpversion, String data
         }
         post {
             always {
-                junit allowEmptyResults: true, testResults: '${env.BUILD_ID}/*.junit/*.xml,${env.BUILD_ID}/*.junit'
-                archiveArtifacts allowEmptyArchive: true, artifacts: '${env.BUILD_ID}/**'
+                junit allowEmptyResults: true, testResults: "${env.BUILD_ID}/*.junit/*.xml,${env.BUILD_ID}/*.junit"
+                archiveArtifacts allowEmptyArchive: true, artifacts: "${env.BUILD_ID}/**"
                 cleanWs deleteDirs: true, notFailBuild: true
             }
         }