Bump ctutils from 0.4.0 to 0.4.2

Bumps [ctutils](https://github.com/RustCrypto/utils) from 0.4.0 to 0.4.2.
- [Commits](RustCrypto/utils@ctutils-v0.4.0...ctutils-v0.4.2)

---
updated-dependencies:
- dependency-name: ctutils
  dependency-version: 0.4.2
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

Signed-off-by: dependabot[bot] <support@github.com>

Author: dependabot[bot]