Revert "temporary switch to hardware slaves"

This reverts commit aa7b43a301db1a255c84ae9224cb4ae0ba315ca1.

Change-Id: Icce80cc3d2a797f2c27566311c43501715b2fcc4
diff --git a/test-system-reclass-pipeline.groovy b/test-system-reclass-pipeline.groovy
index f49b801..72b618b 100644
--- a/test-system-reclass-pipeline.groovy
+++ b/test-system-reclass-pipeline.groovy
@@ -12,8 +12,7 @@
     extraVarsYaml = JsonOutput.toJson(env.getEnvironment().findAll{ it.key.startsWith('GERRIT_') })
 }
 
-//def slaveNode = env.SLAVE_NODE ?: 'python&&docker'
-def slaveNode = env.SLAVE_NODE ?: 'hardware'
+def slaveNode = env.SLAVE_NODE ?: 'virtual'
 def gerritCredentials = env.CREDENTIALS_ID ?: 'gerrit'
 
 def gerritRef = env.GERRIT_REFSPEC ?: null