Bump `TargetRubyVersion: 2.2` since ruby-plsql now only supports Rails 5.0 or higher
Bump `TargetRubyVersion: 2.2` since ruby-plsql now only supports Rails
5.0 or higher

rsim/ruby-plsql,yahonda/ruby-plsql,yahonda/ruby-plsql,rsim/ruby-plsql