Add a note about typeshed to the issue template (#4478)

ilevkivskyi · web-flow · commit 8082af2dff6f · 2018-01-17T23:57:51.000Z
diff --git a/ISSUE_TEMPLATE.md b/ISSUE_TEMPLATE.md
@@ -1,3 +1,7 @@
+Note: if you are reporting a wrong signature of a function or a class in
+the standard library, then the typeshed tracker is better suited
+for this report: https://github.com/python/typeshed/issues
+
 Please provide more information to help us understand the issue:
 
 * Are you reporting a bug, or opening a feature request?
