Bump postgres from 3.4.5 to 3.4.8 in /server

Bumps [postgres](https://github.com/porsager/postgres) from 3.4.5 to 3.4.8.
- [Release notes](https://github.com/porsager/postgres/releases)
- [Changelog](https://github.com/porsager/postgres/blob/master/CHANGELOG.md)
- [Commits](porsager/postgres@v3.4.5...v3.4.8)

---
updated-dependencies:
- dependency-name: postgres
  dependency-version: 3.4.8
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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Author: dependabot[bot]