Use updated discord badge

Author: tekktrik

README.rst

@@ -7,7 +7,7 @@ Introduction
     :alt: Documentation Status
 
 
-.. image:: https://img.shields.io/discord/327254708534116352.svg
+.. image:: https://raw.githubusercontent.com/adafruit/Adafruit_CircuitPython_Bundle/main/badges/adafruit_discord.svg
     :target: https://adafru.it/discord
     :alt: Discord