[chef] PG gem unavailable in Chef 11.6

[Greg Symons < >]

Ohai, Chefs!

So, I'm using the Opscode postgresql cookbook to install the pg gem on 
an omnibus Chef 11.6 install, and when I try to use the gem, it says 
it's unavailable. If I add a `Gem.clear_paths` after including the 
postgresql::ruby recipe, then I'm able to use the gem fine, which sort 
of makes sense. The thing that doesn't make sense is why I don't have to 
do this in Chef 10 (10.16.4, specifically). Has anyone else seen this? 
Is this a bug in Chef or the cookbook?

Thanks,

Greg