Update dependencies

vendor/tailscale.com/util/racebuild/off.go

@@ -0,0 +1,8 @@
+// Copyright (c) Tailscale Inc & AUTHORS
+// SPDX-License-Identifier: BSD-3-Clause
+
+//go:build !race
+
+package racebuild
+
+const On = false

vendor/tailscale.com/util/racebuild/on.go

@@ -0,0 +1,8 @@
+// Copyright (c) Tailscale Inc & AUTHORS
+// SPDX-License-Identifier: BSD-3-Clause
+
+//go:build race
+
+package racebuild
+
+const On = true

vendor/tailscale.com/util/racebuild/racebuild.go

@@ -0,0 +1,6 @@
+// Copyright (c) Tailscale Inc & AUTHORS
+// SPDX-License-Identifier: BSD-3-Clause
+
+// Package racebuild exports a constant about whether the current binary
+// was built with the race detector.
+package racebuild