Merge pull request 'update actual start' (#236) from dev-wahyu into staging

Reviewed-on: ordo/adw-backend#236

app/Http/Controllers/ActivityController.php

@@ -187,7 +187,7 @@ class ActivityController extends Controller
 			$actualStartValues = array_column(array_filter($dataFinal, function($item) {
 				return isset($item['actual_start']);
 			}), 'actual_start');
-			$returnActualStartOrEnd = min($actualStartValues);
+			$returnActualStartOrEnd = count($actualStartValues) > 0 ? min($actualStartValues) : null;
             if (isset($parent)) {
                 $parent->actual_start = $returnActualStartOrEnd;
                 $parent->save();