fix: stable setup-envtest version (#169)

fix: use latest available version

Makefile

@@ -192,7 +192,7 @@ $(CONTROLLER_GEN): $(LOCALBIN)
 .PHONY: envtest
 envtest: $(ENVTEST) ## Download envtest-setup locally if necessary.
 $(ENVTEST): $(LOCALBIN)
-	test -s $(LOCALBIN)/setup-envtest || GOBIN=$(LOCALBIN) go install sigs.k8s.io/controller-runtime/tools/setup-envtest@latest
+	test -s $(LOCALBIN)/setup-envtest || GOBIN=$(LOCALBIN) go install sigs.k8s.io/controller-runtime/tools/setup-envtest@release-0.16
 
 .PHONY: ginkgo
 ginkgo: $(GINKGO) ## Download ginkgo locally if necessary. If wrong version is installed, it will be overwritten.