Fix default EXTRA_FORMULAS logic

Change-Id: Ic5743ed369dd12b1b98622735f0c4f25019886f9
diff --git a/src/com/mirantis/mk/SaltModelTesting.groovy b/src/com/mirantis/mk/SaltModelTesting.groovy
index 6d7b9ad..261990c 100644
--- a/src/com/mirantis/mk/SaltModelTesting.groovy
+++ b/src/com/mirantis/mk/SaltModelTesting.groovy
@@ -34,6 +34,7 @@
     if (!extraFormulas.contains('*') && formulasSource == 'pkg') {
         common.warningMsg("You have passed deprecated variable:extraFormulas=${extraFormulas}. " +
             "\n It would be ignored, and all formulas would be installed anyway")
+        extraFormulas = '*'
     }
     if (!dockerContainerName) {
         dockerContainerName = 'setupAndTestNode' + UUID.randomUUID().toString()