chore: update github issue template

.github/ISSUE_TEMPLATE/feature_request.md

@@ -9,8 +9,6 @@ assignees: ''
 
 <!-- Your issue may already be reported! Please search for it before creating one. -->
 
-<!-- If you are requesting support for the new model, goto [model-request](https://github.com/sigoden/aichat/issues/new?assignees=&labels=enhancement&projects=&template=model_request.md&title=). -->
-
 **Is your feature request related to a problem? Please describe.**
 <!-- A clear and concise description of what the problem is. Ex. I'm always frustrated when [...] -->