add crowdin badge (#8447)

Author: 6543

README.md

@@ -12,6 +12,7 @@
 [![Help Contribute to Open Source](https://www.codetriage.com/go-gitea/gitea/badges/users.svg)](https://www.codetriage.com/go-gitea/gitea)
 [![Become a backer/sponsor of gitea](https://opencollective.com/gitea/tiers/backers/badge.svg?label=backers&color=brightgreen)](https://opencollective.com/gitea)
 [![License: MIT](https://img.shields.io/badge/License-MIT-blue.svg)](https://opensource.org/licenses/MIT)
+[![Crowdin](https://badges.crowdin.net/gitea/localized.svg)](https://crowdin.com/project/gitea)
 
 ## Purpose
 

README_ZH.md

@@ -11,6 +11,7 @@
 [![GitHub release](https://img.shields.io/github/release/go-gitea/gitea.svg)](https://github.com/go-gitea/gitea/releases/latest)
 [![Become a backer/sponsor of gitea](https://opencollective.com/gitea/tiers/backers/badge.svg?label=backers&color=brightgreen)](https://opencollective.com/gitea)
 [![License: MIT](https://img.shields.io/badge/License-MIT-blue.svg)](https://opensource.org/licenses/MIT)
+[![Crowdin](https://badges.crowdin.net/gitea/localized.svg)](https://crowdin.com/project/gitea)
 
 ## 目标