styleguide: fix broken discussion link

The discussion thread link in default comparisons points to an unrelated
thread.

Change-Id: Ib9ee9177d89e0d1c91b00c28b704e7aa98fe74a1
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/5332414
Reviewed-by: danakj <[email protected]>
Commit-Queue: danakj <[email protected]>
Cr-Commit-Position: refs/heads/main@{#1266510}
diff --git a/styleguide/c++/c++-features.md b/styleguide/c++/c++-features.md
index 2def641..bad29f65 100644
--- a/styleguide/c++/c++-features.md
+++ b/styleguide/c++/c++-features.md
@@ -847,7 +847,7 @@
 directly in the header, as this is much simpler to write.
 
 - [Migration bug](https://crbug.com/1414530)
-- [Discussion thread](https://groups.google.com/a/chromium.org/g/cxx/c/JVN4E4IIYA0)
+- [Discussion thread](https://groups.google.com/a/chromium.org/g/cxx/c/h4lVi2jHU-0/m/X0q_Bh2IAAAJ)
 
 ***