Jenkins: Allows for concurrent builds.

On Cloudbees every build is started on a new worker. So no need to
restrict execution.

Jenkinsfile

@@ -12,8 +12,6 @@ node() { // No specific label
   properties([
     // Keep only the last 10 build to preserve space
     buildDiscarder(logRotator(numToKeepStr: '10')),
-    // Don't run concurrent builds for a branch, because they use the same workspace directory
-    disableConcurrentBuilds()
   ])
 
   catchError {