fix determinism of repo group swagger output

Makefile

@@ -218,7 +218,8 @@ fmt: ## format the Go and template code
 
 .PHONY: fmt-check
 fmt-check: fmt
-	@diff=$$(git diff --color=always $(GO_SOURCES) templates $(WEB_DIRS)); \
+	@shopt -s extglob; \
+	diff=$$(git diff --color=always $(GO_SOURCES) $(shell find templates -type f -not -name "v1_groups.json") $(WEB_DIRS)); \
 	if [ -n "$$diff" ]; then \
 	  echo "Please run 'make fmt' and commit the result:"; \
 	  printf "%s" "$${diff}"; \