[release-branch.go1.21] go1.21.4

Change-Id: I3d607ba9f701a76a46f3ab3223fa83e5c517d285
Reviewed-on: https://go-review.googlesource.com/c/go/+/540517
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Auto-Submit: Gopher Robot <gobot@golang.org>
Reviewed-by: Heschi Kreinick <heschi@google.com>
Reviewed-by: Cherry Mui <cherryyz@google.com>
diff --git a/VERSION b/VERSION
index c284f64..74f07e5 100644
--- a/VERSION
+++ b/VERSION
@@ -1,2 +1,2 @@
-go1.21.3
-time 2023-10-09T17:04:35Z
+go1.21.4
+time 2023-11-01T20:46:39Z