Add check to submission filter for Desktop requesting for more than one node

roles/slurm-common/templates/job_submit.lua.j2

@@ -24,6 +24,14 @@ if job_desc.account == "default" then
 end
 
 
+-- Check Desktop requests with more than one node
+
+if ((job_desc.name == "desktop") and (job_desc.min_nodes > 1 )) then
+   slurm.log_user("The current M3 Desktop applications are unable to utilise more than one node, please select one node instead")
+   return slurm.ERROR
+end
+
+
 
 -- Check for gres.gpu requirements in m3c, m3h and m3g, else move job to comp