Update README.md (#251)

install `https://github.com/s-allius/ha-addons` as repro for our add-on

README.md

@@ -435,4 +435,4 @@ We're very happy to receive contributions to this project! You can get started b
 The changelog lives in [CHANGELOG.md](https://github.com/s-allius/tsun-gen3-proxy/blob/main/CHANGELOG.md). It follows the principles of [Keep a Changelog](https://keepachangelog.com/en/1.0.0/).
 
 [repository-badge]: https://img.shields.io/badge/Add%20repository%20to%20my-Home%20Assistant-41BDF5?logo=home-assistant&style=for-the-badge
-[repository-url]: https://my.home-assistant.io/redirect/supervisor_add_addon_repository/?repository_url=https%3A%2F%2Fgithub.com%2Fs-allius%2Ftsun-gen3-proxy
+[repository-url]: https://my.home-assistant.io/redirect/supervisor_add_addon_repository/?repository_url=https%3A%2F%2Fgithub.com%2Fs-allius%2Fha-addons