Bump regex from 1.5.4 to 1.5.6 in /rust
Bump regex from 1.5.4 to 1.5.6 in /rust

Bumps [regex](https://github.com/rust-lang/regex) from 1.5.4 to 1.5.6.
- [Release notes](https://github.com/rust-lang/regex/releases)
- [Changelog](https://github.com/rust-lang/regex/blob/master/CHANGELOG.md)
- [Commits](https://github.com/rust-lang/regex/compare/1.5.4...1.5.6)

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

Signed-off-by: dependabot[bot] <5bdcd3c0d4d24ae3e71b3b452a024c6324c7e4bb@github.com>
wtfleming/data-structures-and-algorithms,wtfleming/data-structures-and-algorithms