Re-enable squeal-postgresql
Re-enable squeal-postgresql

Checklist:
- [ ] Meaningful commit message, eg `add my-cool-package` (please not mention `build-constraints.yml`)
- [ ] At least 30 minutes have passed since uploading to Hackage
- [ ] On your own machine, you have successfully run the following command (replace `$package` with the name of the package that is submitted, and `$version` with the version of the package you want to get into Stackage):

      ./verify-package $package # or $package-$version

The script runs virtually the following commands in a clean directory:

      stack unpack $package-$version  # $version is optional
      cd $package-$version
      rm -f stack.yaml && stack init --resolver nightly
      stack build --resolver nightly --haddock --test --bench --no-run-benchmarks

michalkonecny/stackage,jonschoning/stackage,clinty/stackage,fpco/stackage,soenkehahn/stackage,Daniel-Diaz/stackage,iand675/stackage,massysett/stackage,mrkkrp/stackage,simonmichael/stackage