M14: update ctutils to 0.4.5 for RUSTSEC-2026-0385

The dependency-advisory gate rejects ctutils 0.4.2 (non-constant-time
mask generation and u128 comparisons, fixed in 0.4.4). It comes in
through crypto-bigint for the signing crates. Only its version and
checksum change in Cargo.lock.

(cherry picked from commit 8a687ee2c6)

Cargo.lock

@@ -1291,9 +1291,9 @@ dependencies = [
 
 [[package]]
 name = "ctutils"
-version = "0.4.2"
+version = "0.4.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "7d5515a3834141de9eafb9717ad39eea8247b5674e6066c404e8c4b365d2a29e"
+checksum = "38d28fb6aa7dd680b3ffd1a3e64e115c177bdba63c0ae7f9cd48129ff05c4fa0"
 dependencies = [
  "cmov",
  "subtle",