[3.13] Replace `capi-sig` mailing list with `discuss.python.org` (GH-136211) (#136214)

Replace `capi-sig` mailing list with `discuss.python.org` (GH-136211)
(cherry picked from commit 7afe1adb0089d0f2df2add79bbc2300c2f236d90)

Co-authored-by: sobolevn <mail@sobolevn.me>

diff --git a/Doc/howto/isolating-extensions.rst b/Doc/howto/isolating-extensions.rst
index fbc426ba1d7d9afcac3e3b54460be725cd5e8c3b..7da6dc8a39795e8696f013af2569c5d4bf90be96 100644 (file)
--- a/Doc/howto/isolating-extensions.rst
+++ b/Doc/howto/isolating-extensions.rst
@@ -626,8 +626,7 @@ Open Issues
 
 Several issues around per-module state and heap types are still open.
 
-Discussions about improving the situation are best held on the `capi-sig
-mailing list <https://mail.python.org/mailman3/lists/capi-sig.python.org/>`__.
+Discussions about improving the situation are best held on the `discuss forum under c-api tag <https://discuss.python.org/c/core-dev/c-api/30>`__.
 
 
 Per-Class Scope