Bump num-traits from 0.2.17 to 0.2.18

Bumps [num-traits](https://github.com/rust-num/num-traits) from 0.2.17 to 0.2.18.
- [Changelog](https://github.com/rust-num/num-traits/blob/master/RELEASES.md)
- [Commits](rust-num/num-traits@num-traits-0.2.17...num-traits-0.2.18)

---
updated-dependencies:
- dependency-name: num-traits
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

Signed-off-by: dependabot[bot] <[email protected]>