temporarily allow more stacks

Change-Id: I0fbf03be90153cf1697326826aa5f8898773581c
diff --git a/lab-pipeline.groovy b/lab-pipeline.groovy
index 499c615..36645a8 100644
--- a/lab-pipeline.groovy
+++ b/lab-pipeline.groovy
@@ -47,7 +47,7 @@
 salt = new com.mirantis.mk.Salt()
 test = new com.mirantis.mk.Test()
 
-_MAX_PERMITTED_STACKS = 2
+_MAX_PERMITTED_STACKS = 20
 overwriteFile = "/srv/salt/reclass/classes/cluster/overwrite.yml"
 
 timestamps {