Bumps [rustc-demangle](https://github.com/alexcrichton/rustc-demangle) from 0.1.4 to 0.1.16.
- [Release notes](https://github.com/alexcrichton/rustc-demangle/releases)
- [Commits](alexcrichton/rustc-demangle@0.1.4...0.1.16)

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