Add copyright and blank line

Author: 42wim

integrations/api_httpsig_test.go

@@ -1,3 +1,7 @@
+// Copyright 2022 The Gitea Authors. All rights reserved.
+// Use of this source code is governed by a MIT-style
+// license that can be found in the LICENSE file.
+
 package integrations
 
 import (
@@ -8,6 +12,7 @@ import (
 	"testing"
 
 	api "code.gitea.io/gitea/modules/structs"
+
 	"github.com/go-fed/httpsig"
 	"golang.org/x/crypto/ssh"
 )