tweak MooseTestApp registry call
tweak MooseTestApp registry call

follow up to #10952

lindsayad/moose,dschwen/moose,nuclear-wizard/moose,idaholab/moose,permcody/moose,andrsd/moose,idaholab/moose,lindsayad/moose,laagesen/moose,dschwen/moose,dschwen/moose,bwspenc/moose,SudiptaBiswas/moose,permcody/moose,jessecarterMOOSE/moose,sapitts/moose,idaholab/moose,laagesen/moose,YaqiWang/moose,lindsayad/moose,harterj/moose,milljm/moose,sapitts/moose,milljm/moose,laagesen/moose,sapitts/moose,YaqiWang/moose,bwspenc/moose,permcody/moose,harterj/moose,lindsayad/moose,bwspenc/moose,jessecarterMOOSE/moose,harterj/moose,permcody/moose,YaqiWang/moose,sapitts/moose,jessecarterMOOSE/moose,harterj/moose,lindsayad/moose,nuclear-wizard/moose,bwspenc/moose,jessecarterMOOSE/moose,milljm/moose,milljm/moose,SudiptaBiswas/moose,idaholab/moose,idaholab/moose,dschwen/moose,SudiptaBiswas/moose,andrsd/moose,dschwen/moose,andrsd/moose,SudiptaBiswas/moose,nuclear-wizard/moose,nuclear-wizard/moose,andrsd/moose,andrsd/moose,milljm/moose,bwspenc/moose,laagesen/moose,laagesen/moose,sapitts/moose,jessecarterMOOSE/moose,YaqiWang/moose,SudiptaBiswas/moose,harterj/moose