docs: Fix more Discord links

Author: nickserv

.github/ISSUE_TEMPLATE.md

@@ -24,8 +24,8 @@ Thanks for your interest in the project. We appreciate bugs filed and PRs submit
   codesandbox to make a reproduction of your issue: https://kcd.im/rtl-help
   * React Spectrum
     https://spectrum.chat/testing-library
-  * Reactiflux on Discord
-    https://www.reactiflux.com
+  * Discord
+    https://discord.gg/c6JN9fM
   * Stack Overflow
     https://stackoverflow.com/questions/tagged/react-testing-library
 

.github/ISSUE_TEMPLATE/Question.md

@@ -17,7 +17,7 @@ instead of filing an issue on GitHub. You can follow the instructions in this
 codesandbox to make a reproduction of your issue: https://kcd.im/rtl-help
 
 - React Spectrum https://spectrum.chat/react-testing-library
-- Reactiflux on Discord https://www.reactiflux.com
+- Discord https://discord.gg/c6JN9fM
 - Stack Overflow
   https://stackoverflow.com/questions/tagged/react-testing-library
 - Documentation: https://github.com/testing-library/testing-library-docs