rotate the slurm log correctly

Former-commit-id: f4e47d94

roles/slurm-common/templates/slurmlog.j2

@@ -20,9 +20,9 @@
 {% if ansible_os_family == 'RedHat' and ansible_distribution_version >= '7' %}
  postrotate
 {% if slurmctrl == inventory_hostname %}
-   {{ slurm_dir }}/sbin/slurmctld flushlogs 1>/dev/null || true
+  systemctl kill -s HUP --kill-who=main slurmctld
 {% else %}
-   {{ slurm_dir }}/sbin/slurmd flushlogs 1>/dev/null || true
+  systemctl kill -s HUP --kill-who=main slurmd
 {% endif %}
 {% else %}
  postrotate /etc/init.d/slurm reconfig