guide users to GH discussions for usage questions

I hope this allows us to:

- focus issues to bug, enhancement, question discussions specific to this project (i.e. bugs in this Go library, not the CPython C-API)
- allow any kind of broad discussion how to achieve specific things using this library alongside the CPython C-API in Github Discussions

.github/ISSUE_TEMPLATE.md

@@ -1,9 +1,17 @@
-**Describe what happened:**
 
+------
 
-**Describe what you expected:**
+Note: If you have a **usage question** (i.e. how to achieve something specific using this library + the CPython C-API) consider posting it to [this project's **GitHub Discussions** board](https://github.com/go-python/cpy3/discussions) instead of creating an issue. Any question is welcome!
 
+------
 
-**Steps to reproduce the issue:**
-
+**Describe what happened:**   
+
+
+**Describe what you expected:**   
+
+
+**Steps to reproduce the issue:**   
+
+