Fix warning about comma at the end of enumerator lists.
Fix warning about comma at the end of enumerator lists.

Refs #1777.

wgapl/moose,Chuban/moose,raghavaggarwal/moose,friedmud/moose,yipenggao/moose,Chuban/moose,liuwenf/moose,permcody/moose,wgapl/moose,laagesen/moose,permcody/moose,xy515258/moose,wgapl/moose,markr622/moose,dschwen/moose,mellis13/moose,jessecarterMOOSE/moose,nuclear-wizard/moose,Chuban/moose,danielru/moose,jasondhales/moose,harterj/moose,harterj/moose,stimpsonsg/moose,andrsd/moose,dschwen/moose,jiangwen84/moose,jiangwen84/moose,capitalaslash/moose,capitalaslash/moose,dschwen/moose,backmari/moose,lindsayad/moose,andrsd/moose,jbair34/moose,stimpsonsg/moose,raghavaggarwal/moose,giopastor/moose,Chuban/moose,stimpsonsg/moose,lindsayad/moose,markr622/moose,katyhuff/moose,wgapl/moose,jasondhales/moose,bwspenc/moose,laagesen/moose,sapitts/moose,lindsayad/moose,SudiptaBiswas/moose,kasra83/moose,kasra83/moose,dschwen/moose,danielru/moose,liuwenf/moose,backmari/moose,liuwenf/moose,waxmanr/moose,nuclear-wizard/moose,jessecarterMOOSE/moose,milljm/moose,mellis13/moose,katyhuff/moose,yipenggao/moose,laagesen/moose,sapitts/moose,jasondhales/moose,giopastor/moose,sapitts/moose,jhbradley/moose,backmari/moose,lindsayad/moose,backmari/moose,waxmanr/moose,YaqiWang/moose,xy515258/moose,capitalaslash/moose,raghavaggarwal/moose,SudiptaBiswas/moose,bwspenc/moose,joshua-cogliati-inl/moose,yipenggao/moose,waxmanr/moose,danielru/moose,liuwenf/moose,jbair34/moose,andrsd/moose,jasondhales/moose,joshua-cogliati-inl/moose,SudiptaBiswas/moose,milljm/moose,milljm/moose,jessecarterMOOSE/moose,YaqiWang/moose,harterj/moose,SudiptaBiswas/moose,jbair34/moose,idaholab/moose,katyhuff/moose,jessecarterMOOSE/moose,jiangwen84/moose,stimpsonsg/moose,jhbradley/moose,bwspenc/moose,permcody/moose,joshua-cogliati-inl/moose,markr622/moose,andrsd/moose,jbair34/moose,bwspenc/moose,harterj/moose,xy515258/moose,permcody/moose,raghavaggarwal/moose,milljm/moose,adamLange/moose,YaqiWang/moose,idaholab/moose,jessecarterMOOSE/moose,liuwenf/moose,jhbradley/moose,jiangwen84/moose,liuwenf/moose,jhbradley/moose,capitalaslash/moose,YaqiWang/moose,adamLange/moose,idaholab/moose,mellis13/moose,yipenggao/moose,joshua-cogliati-inl/moose,waxmanr/moose,andrsd/moose,dschwen/moose,adamLange/moose,katyhuff/moose,laagesen/moose,laagesen/moose,markr622/moose,nuclear-wizard/moose,adamLange/moose,lindsayad/moose,harterj/moose,xy515258/moose,sapitts/moose,friedmud/moose,giopastor/moose,friedmud/moose,nuclear-wizard/moose,friedmud/moose,idaholab/moose,kasra83/moose,giopastor/moose,SudiptaBiswas/moose,bwspenc/moose,danielru/moose,milljm/moose,kasra83/moose,mellis13/moose,idaholab/moose,sapitts/moose