Fix exception definition

Change-Id: Ibbeedcea8d40ef9ef98614852e0810c863448c65
diff --git a/lab-pipeline.groovy b/lab-pipeline.groovy
index 110dd12..2db1608 100644
--- a/lab-pipeline.groovy
+++ b/lab-pipeline.groovy
@@ -57,7 +57,7 @@
 } catch (MissingPropertyException e) {
   try {
     STACK_INSTALL = INSTALL
-  } catch (MissingPropertyException e) {
+  } catch (MissingPropertyException e2) {
     common.errorMsg("Property STACK_INSTALL or INSTALL not found!")
   }
 }