Bump msgpack from 1.5.4 to 1.5.6
Bump msgpack from 1.5.4 to 1.5.6

Bumps [msgpack](https://github.com/msgpack/msgpack-ruby) from 1.5.4 to 1.5.6.
- [Release notes](https://github.com/msgpack/msgpack-ruby/releases)
- [Changelog](https://github.com/msgpack/msgpack-ruby/blob/master/ChangeLog)
- [Commits](https://github.com/msgpack/msgpack-ruby/compare/v1.5.4...v1.5.6)

---
updated-dependencies:
- dependency-name: msgpack
  dependency-type: indirect
  update-type: version-update:semver-patch
...

Signed-off-by: dependabot[bot] <5bdcd3c0d4d24ae3e71b3b452a024c6324c7e4bb@github.com>
lopopolo/dotfiles,lopopolo/dotfiles