Add whitespace linter (#24855)

server/public/model/incoming_webhook.go

@@ -61,7 +61,6 @@ type IncomingWebhookRequest struct {
 func (o *IncomingWebhook) IsValid() *AppError {
 	if !IsValidId(o.Id) {
 		return NewAppError("IncomingWebhook.IsValid", "model.incoming_hook.id.app_error", nil, "", http.StatusBadRequest)
-
 	}
 
 	if o.CreateAt == 0 {