Bump juniper from 0.15.9 to 0.16.1

Bumps [juniper](https://github.com/graphql-rust/juniper) from 0.15.9 to 0.16.1.
- [Release notes](https://github.com/graphql-rust/juniper/releases)
- [Changelog](https://github.com/graphql-rust/juniper/blob/master/release.toml)
- [Commits](graphql-rust/juniper@juniper-v0.15.9...juniper-v0.16.1)

---
updated-dependencies:
- dependency-name: juniper
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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

Author: dependabot[bot]