Bump cpp_demangle from 0.2.9 to 0.2.12

Bumps [cpp_demangle](https://github.com/gimli-rs/cpp_demangle) from 0.2.9 to 0.2.12.
- [Release notes](https://github.com/gimli-rs/cpp_demangle/releases)
- [Changelog](https://github.com/gimli-rs/cpp_demangle/blob/master/CHANGELOG.md)
- [Commits](https://github.com/gimli-rs/cpp_demangle/commits)

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

Author: dependabot-support

Cargo.lock

@@ -12,7 +12,7 @@ version = "0.2.0"
 path = "./ir.rs"
 
 [dependencies]
-cpp_demangle = { version = "0.2.7", default-features = false }
+cpp_demangle = { version = "0.2.12", default-features = false }
 frozen = "1"
 petgraph = "0.4.12"
 rustc-demangle = "0.1.5"