Add production hint

Change-Id: I5e29b6fc69edd2f03f49e979f4842c1f88f5269f
diff --git a/service.go b/service.go
index 2fac3c1..ad6afaf 100644
--- a/service.go
+++ b/service.go
@@ -180,6 +180,8 @@
 }
 
 func main() {
+	gin.SetMode(gin.ReleaseMode)
+
 	if godotenv.Load() != nil {
 		log.Println(".env file not loaded.")
 	}