Bump ryu from 1.0.5 to 1.0.6

Bumps [ryu](https://github.com/dtolnay/ryu) from 1.0.5 to 1.0.6.
- [Release notes](https://github.com/dtolnay/ryu/releases)
- [Commits](dtolnay/ryu@1.0.5...1.0.6)

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

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