fix discord link

Author: MoOx

docs/migration/jsx3.md

@@ -109,7 +109,7 @@ knowing 🤷‍
 ## Need help to migrate ?
 
 If you struggle with it & have questions,
-[reach us on our discord server](https://reasonml-community.github.io/reason-react-native/discord/)
+[reach us on our discord server](https://reason-react-native.github.io/discord/)
 
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