📝 Replace Twitter with Fosstodon

Author: thinkyhead

README.md

@@ -9,7 +9,7 @@
     <a href="https://github.com/MarlinFirmware/Marlin/actions"><img alt="CI Status" src="https://github.com/MarlinFirmware/Marlin/actions/workflows/test-builds.yml/badge.svg"></a>
     <a href="https://github.com/sponsors/thinkyhead"><img alt="GitHub Sponsors" src="https://img.shields.io/github/sponsors/thinkyhead?color=db61a2"></a>
     <br />
-    <a href="https://twitter.com/MarlinFirmware"><img alt="Follow MarlinFirmware on Twitter" src="https://img.shields.io/twitter/follow/MarlinFirmware?style=social&logo=twitter"></a>
+    <a href="https://fosstodon.org/@marlinfirmware"><img alt="Follow MarlinFirmware on Mastodon" src="https://img.shields.io/mastodon/follow/109450200866020466?domain=https%3A%2F%2Ffosstodon.org&logoColor=%2300B&style=social"></a>
 </p>
 
 Additional documentation can be found at the [Marlin Home Page](https://marlinfw.org/).