Bump pg from 1.4.2 to 1.4.3

Bumps [pg](https://github.com/ged/ruby-pg) from 1.4.2 to 1.4.3.
- [Release notes](https://github.com/ged/ruby-pg/releases)
- [Changelog](https://github.com/ged/ruby-pg/blob/master/History.rdoc)
- [Commits](https://github.com/ged/ruby-pg/compare/v1.4.2...v1.4.3

)

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

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