[release-branch.go1.21] go1.21.13

Change-Id: I81cedc777e43503322e96ec45a4c473266429f40
Reviewed-on: https://go-review.googlesource.com/c/go/+/603398


Reviewed-by: David Chase <drchase@google.com>
Auto-Submit: Gopher Robot <gobot@golang.org>
Reviewed-by: Michael Knyszek <mknyszek@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>

VERSION

-go1.21.12
-time 2024-06-27T20:11:12Z
+go1.21.13
+time 2024-07-31T19:43:06Z