jinja template wasn't working well with undefined variables

roles/slurm-from-source/templates/slurm.conf.j2

@@ -98,7 +98,7 @@ SlurmSchedLogFile={{ slurmschedlog.log }}
 JobCompType=jobcomp/none
 #JobCompLoc=
 #
-{% if slurmjob %}
+{% if slurmjob is defined %}
 Prolog={{ slurmjob.prolog }}
 Epilog={{ slurmjob.epilog }}
 {% endif %}

roles/slurmdb/templates/slurmdbd.conf.j2

@@ -22,7 +22,7 @@ DbdHost={{ slurmctrl }}
 SlurmUser=slurm
 #MessageTimeout=300
 #DefaultQOS=normal,standby
-{% if slurmdbdlog %}
+{% if slurmdbdlog is defined %}
 DebugLevel={{ slurmdbdlog.level }}
 LogFile={{ slurmdbdlog.log }}
 {% else %}