[release-branch.go1.21] go1.21.12

Change-Id: I5d0af46471907bc3d28f18348bb208689e4d9949
Reviewed-on: https://go-review.googlesource.com/c/go/+/596256


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

VERSION

-go1.21.11
-time 2024-05-30T19:26:07Z
+go1.21.12
+time 2024-06-27T20:11:12Z