Issue #3403196 by bluegeek9, andileco, emircan erkul, jaymehls: PHP 8.2 error on chart type

Closes #3403196

modules/charts_billboard/src/Plugin/chart/Billboard.php

@@ -209,7 +209,7 @@ class Billboard extends AbstractChart {
     }
 
     // Determines if chart is stacked.
-    if (!empty($options['grouping'] && $options['grouping'] == TRUE)) {
+    if (!empty($options['grouping']) && $options['grouping'] == TRUE) {
       $seriesNames = [];
       for ($i = 0; $i < $seriesCount; $i++) {
         array_push($seriesNames, $seriesData[$i]['name']);