Fix 'make fmt-check'

`make fmt-check` did not run all commands that `make fmt` did, resulting
in missed diffs. Fix that by just depending on the `fmt` target.

Includes: #18633

Author: silverwind

Makefile

@@ -284,9 +284,8 @@ errcheck:
 	@errcheck $(GO_PACKAGES)
 
 .PHONY: fmt-check
-fmt-check:
-	# get all go files and run gitea-fmt (with gofmt) on them
-	@diff=$$($(GO) run build/code-batch-process.go gitea-fmt -s -d '{file-list}'); \
+fmt-check: fmt
+	@diff=$$(git diff $(GO_DIRS)); \
 	if [ -n "$$diff" ]; then \
 		echo "Please run 'make fmt' and commit the result:"; \
 		echo "$${diff}"; \

services/mailer/mail_test.go

@@ -17,6 +17,7 @@ import (
 	"code.gitea.io/gitea/models/unittest"
 	user_model "code.gitea.io/gitea/models/user"
 	"code.gitea.io/gitea/modules/setting"
+
 	"github.com/stretchr/testify/assert"
 )