chore: upgrade controller-gen to 0.4.1

we want minProperties/maxProperties validation, see here:
https://github.com/kubernetes-sigs/controller-tools/releases/tag/v0.4.1
and
https://github.com/kubernetes-sigs/controller-tools/pull/488/files

Makefile

@@ -71,7 +71,7 @@ ifeq (, $(shell which controller-gen))
 	CONTROLLER_GEN_TMP_DIR=$$(mktemp -d) ;\
 	cd $$CONTROLLER_GEN_TMP_DIR ;\
 	go mod init tmp ;\
-	go get sigs.k8s.io/controller-tools/cmd/controller-gen@v0.2.5 ;\
+	go get sigs.k8s.io/controller-tools/cmd/controller-gen@v0.4.1 ;\
 	rm -rf $$CONTROLLER_GEN_TMP_DIR ;\
 	}
 CONTROLLER_GEN=$(GOBIN)/controller-gen