MC-23228: A wrong behaviour of a chart order

Author: viktorpetryk

app/code/Magento/Backend/Block/Dashboard/Graph.php

@@ -237,7 +237,7 @@ public function getChartUrl($directUrl = true)
                 case '1y':
                 case '2y':
                     $d = $dateStart->format('Y-m');
-                    $dateStart->modify('+1 month');
+                    $dateStart->modify('first day of next month');
                     break;
                 default:
                     $d = $dateStart->format('Y-m-d H:00');