Corrected Nokia port-threshold

SROS port-threshold is not equal to min-links
It is a value at which an action is taken, i.e. (min-links - 1).
E.g. AE min-links is set to 2 in Junos, then in SROS port-threshold must be 1 to achieve the same behaviour.

geant/gap_ansible/roles/iptrunk/templates/nokia/trunk_interface.j2

@@ -59,7 +59,7 @@
 {% endfor %}
           {% if (common.minimum_links | int) > 1 %}
           <port-threshold>
-            <value>{{ common.minimum_links }}</value>
+            <value>{{ (common.minimum_links | int) - 1 }}</value>
             <action>down</action>
           </port-threshold>
           {% endif %}