in_region already checks the id, so remove extra check

in_region already checks to see it the id is specified.  We can remove
this extra check and let in_region take care of that
From reading the code, I think the idea was to be able to default to the current region for local regions, but be able to pass nil so that the master region can see all of the classifications.  In the master region, we show the superset of all classifications across all of the subordinate regions.  However, I thought we required the customers to redefine the ones they wanted at the master region, so I'm not sure why the nil would be needed.  @dclarizio @h-kataria Can you remember or give any more details?