Display a message instead of empty service matrix

refs #6535

modules/monitoring/application/views/scripts/list/servicematrix.phtml

@@ -21,6 +21,11 @@ $hasHeader = false;
 $pivotData = $this->pivot->toArray();
 $hostFilter = '(' . implode('|', array_keys($pivotData)) . ')';
 ?>
+
+<?php if (sizeof($pivotData) === 0): ?>
+    <?= $this->translate('No Service Found'); ?>
+<?php endif ?>
+
 <?php foreach ($pivotData as $host_name => $serviceStates): ?>
 <?php if (!$hasHeader): ?>
     <thead>