Bump tokio-postgres from 0.7.10 to 0.7.11

Bumps [tokio-postgres](https://github.com/sfackler/rust-postgres) from 0.7.10 to 0.7.11.
- [Release notes](https://github.com/sfackler/rust-postgres/releases)
- [Commits](rust-postgres/rust-postgres@tokio-postgres-v0.7.10...tokio-postgres-v0.7.11)

---
updated-dependencies:
- dependency-name: tokio-postgres
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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Author: dependabot[bot]