internal: update issue template configuration (#8908)

Author: christian-bromann

.github/ISSUE_TEMPLATE/config.yml

@@ -1,6 +1,8 @@
 blank_issues_enabled: false
-version: 2.1
 contact_links:
+  - name: Documentation
+    url: https://github.com/langchain-ai/docs/issues/new?template=langchain.yml
+    about: Report an issue related to the LangChain documentation
   - name: LangChain Forum
     url: https://forum.langchain.com/
-    about: General community discussions, support, and feature requests
+    about: General community discussions and support