Fix returning value

Change-Id: I096b1760f77538f4c6a6d42b4aca0dbc2fca9da0
diff --git a/src/com/mirantis/mk/Common.groovy b/src/com/mirantis/mk/Common.groovy
index 74c80f3..0e956d5 100644
--- a/src/com/mirantis/mk/Common.groovy
+++ b/src/com/mirantis/mk/Common.groovy
@@ -468,8 +468,6 @@
 
 def filterKitchenEnvs(input = []) {
     def variablesList = input[0].split().flatten().sort()
-    def result = []
     variablesList.removeAll { it.toUpperCase().contains('SUITE') }
-    result[0] = variablesList.join(' ')
-    return result
+    return variablesList.join(' ')
 }
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