Bump pg from 0.13.2 to 0.21.0
Bump pg from 0.13.2 to 0.21.0

Bumps [pg](https://bitbucket.org/ged/ruby-pg) from 0.13.2 to 0.21.0.
- [Changelog](https://bitbucket.org/ged/ruby-pg/src/master/History.rdoc)
- [Commits](https://bitbucket.org/ged/ruby-pg/branches/compare/v0.21.0..v0.13.2)

Signed-off-by: dependabot[bot] <5bdcd3c0d4d24ae3e71b3b452a024c6324c7e4bb@dependabot.com>
Matt-Yorkley/openfoodnetwork,openfoodfoundation/openfoodnetwork,lin-d-hop/openfoodnetwork,lin-d-hop/openfoodnetwork,mkllnk/openfoodnetwork,Matt-Yorkley/openfoodnetwork,mkllnk/openfoodnetwork,openfoodfoundation/openfoodnetwork,mkllnk/openfoodnetwork,Matt-Yorkley/openfoodnetwork,Matt-Yorkley/openfoodnetwork,openfoodfoundation/openfoodnetwork,lin-d-hop/openfoodnetwork,mkllnk/openfoodnetwork,openfoodfoundation/openfoodnetwork,lin-d-hop/openfoodnetwork