Add Makefile to test integrations

Signed-off-by: leigh capili <leigh@null.net>

manifests/integrations/Makefile

+
+bases := $(shell dirname $(shell find | grep kustomization.yaml | sort))
+
+all: $(bases)
+
+permutations := $(bases) $(addsuffix /,$(bases))
+.PHONY: $(permutations)
+$(permutations):
+	@echo $@
+	@warnings=$$(kustomize build $@ -o /dev/null 2>&1); \
+		if [ "$$warnings" ]; then \
+			echo "$$warnings"; \
+			false; \
+		fi