fix batch job execution (trac https://trac.osgeo.org/grass/ticket/1074)

git-svn-id: https://svn.osgeo.org/grass/grass/trunk@42343 15284696-431f-4ddb-bdfa-cd5b030d7da7

lib/init/grass.py

@@ -608,7 +608,7 @@ def check_batch_job():
 	else:
 	    message(_("Executing '%s' ...") % batch_job)
 	    grass_gui = "text"
-	    shell = batch_job
+	    os.system(batch_job)
 
 def start_gui():
     # Start the chosen GUI but ignore text