Bump regex from 1.3.7 to 1.8.4 in /coreaudio-sys-utils

Bumps [regex](https://github.com/rust-lang/regex) from 1.3.7 to 1.8.4.
- [Release notes](https://github.com/rust-lang/regex/releases)
- [Changelog](https://github.com/rust-lang/regex/blob/master/CHANGELOG.md)
- [Commits](rust-lang/regex@regex-1.3.7...1.8.4)

---
updated-dependencies:
- dependency-name: regex
  dependency-version: 1.8.4
  dependency-type: indirect
...

Signed-off-by: dependabot[bot] <[email protected]>

Author: dependabot[bot]