fix hostname of cobald slurm node

made cobald be able to run slurm jobs, previously failing with
permission denied.

roles/slurm/templates/slurm.conf.j2

@@ -165,6 +165,8 @@ SlurmSchedLogFile={{slurm_log_path_sched}}
 # COMPUTE NODES
 NodeName=slurm-exec[1-{{num_nodes}}] CPUs=2 CoresPerSocket=2 State=UNKNOWN
 {% for i in alloc_nodes -%}
-NodeName={{i}} State=UNKNOWN
+NodeName={{i.name}}
+	{%- if i.hostname is defined %} NodeHostname={{i.hostname}} {% endif %}
+	State=UNKNOWN
 {% endfor %}
-PartitionName=debug Nodes=slurm-exec[1-{{num_nodes}}] AllocNodes={{alloc_nodes | join(',')}} Default=YES MaxTime=INFINITE State=UP
+PartitionName=debug Nodes=slurm-exec[1-{{num_nodes}}] AllocNodes={{alloc_nodes |map(attribute='name') | join(',')}} Default=YES MaxTime=INFINITE State=UP