Save vvelero image tarball only for velero namespace in docker registry

Signed-off-by: danfengl <[email protected]>

Makefile

@@ -210,10 +210,15 @@ endif
 	-f $(VELERO_DOCKERFILE) .
 	@echo "container: $(IMAGE):$(VERSION)"
 ifeq ($(BUILDX_OUTPUT_TYPE), registry)
+ifeq ($(REGISTRY), velero)
+    @echo "save velero image tarball $(IMAGE):$(VERSION)"
 	@docker pull $(IMAGE):$(VERSION)
+	@echo "remove velero image tarball $(BIN)-$(VERSION).tar if it exist already"
+	@rm -f $(BIN)-$(VERSION).tar
 	@docker save $(IMAGE):$(VERSION) -o $(BIN)-$(VERSION).tar
 	@gzip $(BIN)-$(VERSION).tar
 endif
+endif
 
 SKIP_TESTS ?=
 test: build-dirs