Modify: use path package in app level

pkg/filesystem/remote/handler_test.go

@@ -29,6 +29,7 @@ func TestHandler_Token(t *testing.T) {
 			OptionsSerialized: model.PolicyOption{
 				FileType: []string{"txt"},
 			},
+			Server: "http://test.com",
 		},
 		AuthInstance: auth.HMACAuth{},
 	}
@@ -42,6 +43,7 @@ func TestHandler_Token(t *testing.T) {
 		asserts.NoError(err)
 		policy, err := serializer.DecodeUploadPolicy(credential.Policy)
 		asserts.NoError(err)
+		asserts.Equal("http://test.com/api/v3/callback/remote/123", policy.CallbackURL)
 		asserts.Equal(uint64(10), policy.MaxSize)
 		asserts.Equal(true, policy.AutoRename)
 		asserts.Equal("dir", policy.SavePath)