Update makefile for chart packaging

This change adds a new makefile target to be utilized by the
chart publishing job, specifically one that is compatible with
helm 3. This should fix the publish job not posting
tarballs.

Depends-On: https://review.opendev.org/765634

Change-Id: I3551f691e6c3221b8afb201d8030be538424161b

Makefile

@@ -38,6 +38,10 @@ lint-%: init-%
 build-%: lint-%
 	if [ -d $* ]; then helm package $*; fi
 
+# This is used exclusively with helm3 building in the gate to publish
+package-%: init-%
+	if [ -d $* ]; then helm package $*; fi
+
 clean:
 	@echo "Clean all build artifacts"
 	rm -f */templates/_partials.tpl */templates/_globals.tpl