runTask: Collect output using sh()

vars/runTask.groovy

@@ -50,7 +50,11 @@ def call(String task, String branch, String repo, String phpversion, String data
 
             stage("Detect Moodle Version") {
                 steps {
-                    moodleversion = sh grep "\$branch" moodle/version.php | sed "s/^[^']*'\\([^']*\\).*\$/\\1/"
+                    moodleversion = sh (
+                        script: 'grep "\$branch" moodle/version.php | sed
+                        "s/^[^']*'\\([^']*\\).*\$/\\1/"',
+                        returnStdout: true
+                    ).trim()
                     runner = "${env.PATHTORUNNER}/${moodleversion}"
                     if (!fileExists(runner)) {
                         runner  "${env.PATHTORUNNER}/master"