Update dependencies

vendor/tailscale.com/util/groupmember/groupmember.go

@@ -0,0 +1,29 @@
+// Copyright (c) Tailscale Inc & AUTHORS
+// SPDX-License-Identifier: BSD-3-Clause
+
+// Package groupmember verifies group membership of the provided user on the
+// local system.
+package groupmember
+
+import (
+	"os/user"
+	"slices"
+)
+
+// IsMemberOfGroup reports whether the provided user is a member of
+// the provided system group.
+func IsMemberOfGroup(group, userName string) (bool, error) {
+	u, err := user.Lookup(userName)
+	if err != nil {
+		return false, err
+	}
+	g, err := user.LookupGroup(group)
+	if err != nil {
+		return false, err
+	}
+	ugids, err := u.GroupIds()
+	if err != nil {
+		return false, err
+	}
+	return slices.Contains(ugids, g.Gid), nil
+}