Bump pg gem from 1.1.3 to 1.1.4
Bump pg gem from 1.1.3 to 1.1.4

This keeps the version used by gitlab-monitor and GitLab CE
consistent. This release also adds Ruby 2.6 support and PostgreSQL 11
error codes:

https://github.com/ged/ruby-pg/blob/master/History.rdoc

mmkassem/gitlabhq,iiet/iiet-git,stoplightio/gitlabhq,mmkassem/gitlabhq,mmkassem/gitlabhq,iiet/iiet-git,iiet/iiet-git,stoplightio/gitlabhq,stoplightio/gitlabhq,mmkassem/gitlabhq,stoplightio/gitlabhq,iiet/iiet-git