Fix GroupHandler/WhatFailureGroupHandler to use ProcessableHandlerTrait helper always

src/Monolog/Handler/GroupHandler.php

@@ -80,10 +80,7 @@ class GroupHandler extends Handler implements ProcessableHandlerInterface, Reset
         if ($this->processors) {
             $processed = [];
             foreach ($records as $record) {
-                foreach ($this->processors as $processor) {
-                    $record = call_user_func($processor, $record);
-                }
-                $processed[] = $record;
+                $processed[] = $this->processRecord($record);
             }
             $records = $processed;
         }

src/Monolog/Handler/WhatFailureGroupHandler.php

@@ -25,9 +25,7 @@ class WhatFailureGroupHandler extends GroupHandler
     public function handle(array $record): bool
     {
         if ($this->processors) {
-            foreach ($this->processors as $processor) {
-                $record = call_user_func($processor, $record);
-            }
+            $record = $this->processRecord($record);
         }
 
         foreach ($this->handlers as $handler) {
@@ -49,10 +47,7 @@ class WhatFailureGroupHandler extends GroupHandler
         if ($this->processors) {
             $processed = array();
             foreach ($records as $record) {
-                foreach ($this->processors as $processor) {
-                    $record = call_user_func($processor, $record);
-                }
-                $processed[] = $record;
+                $processed[] = $this->processRecord($record);
             }
             $records = $processed;
         }