Run 'make test' verify job on ubuntu 18.04 instead of 16.04

Change-Id: If570bb8cc19b2eab5877a20c963e27e410ee7560
Signed-off-by: Damjan Marion <damarion@cisco.com>
diff --git a/Makefile b/Makefile
index 36c7a5a..1a409f6 100644
--- a/Makefile
+++ b/Makefile
@@ -569,7 +569,7 @@
 	@make -C build-root PLATFORM=vpp TAG=vpp vom-install
 	$(call banner,"Building $(PKG) packages")
 	@make pkg-$(PKG)
-ifeq ($(OS_ID)-$(OS_VERSION_ID),ubuntu-16.04)
+ifeq ($(OS_ID)-$(OS_VERSION_ID),ubuntu-18.04)
 	$(call banner,"Running tests")
 	@make COMPRESS_FAILED_TEST_LOGS=yes RETRIES=3 test
 endif