Adding stc prerequisites to onos-test

Change-Id: Id18c8dc61a533f3f2e6ee4b5341bbc457bb634e1
diff --git a/tools/build/onos-test b/tools/build/onos-test
index 5edc913..b6f4b20 100755
--- a/tools/build/onos-test
+++ b/tools/build/onos-test
@@ -10,6 +10,5 @@
 
 nodes=$(env | sort | egrep "OC[0-9]+" | cut -d= -f2)
 
-onos-package
-stc setup
+onos-package && stc prerequisites && stc setup