Update issue templates to point to the Discourse forum

Author: ymodak

.github/ISSUE_TEMPLATE/feature_request.yml

@@ -5,7 +5,7 @@ body:
   - type: markdown
     attributes:
       value: >
-        **Note:** If this is a support question (e.g. _How do I do XYZ?_), please post on the [Google Developers Community](https://discord.gg/google-dev-community) Discord server's #palm-api channel instead. This is a great place to interact with developers, and to learn, share, and support each other.
+        **Note:** If this is a support question (e.g. _How do I do XYZ?_), please visit the [Discourse forum](https://discuss.ai.google.dev/). This is a great place to interact with developers, and to learn, share, and support each other.
   - type: textarea
     id: description
     attributes: