Supress error message if git is not available
Supress error message if git is not available

It can happen that git may not be available when building the code, then
users will see about 6 error messages that git is not available.  This
is supressing the messages.

Closes #10429

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