[BUGFIX] Use correct check for disabled field in DataHandler

Instead of checking for the array key `enablecolumns` the check must be
done on the field `disabled` itself.

Resolves: #97728
Releases: main, 11.5
Change-Id: I411b37d4d63eb1ad52592cd887a95c2552ab7bfa
Reviewed-on: https://review.typo3.org/c/Packages/TYPO3.CMS/+/74762
Tested-by: core-ci <typo3@b13.com>
Tested-by: Stefan Bürk <stefan@buerk.tech>
Reviewed-by: Stefan Bürk <stefan@buerk.tech>

typo3/sysext/core/Classes/DataHandling/DataHandler.php

@@ -3272,7 +3272,7 @@ public function copyRecord($table, $uid, $destPid, $first = false, $overrideValu
 
         // Initializing:
         $theNewID = StringUtility::getUniqueId('NEW');
-        $enableField = isset($GLOBALS['TCA'][$table]['ctrl']['enablecolumns']) ? $GLOBALS['TCA'][$table]['ctrl']['enablecolumns']['disabled'] : '';
+        $enableField = $GLOBALS['TCA'][$table]['ctrl']['enablecolumns']['disabled'] ?? '';
         $headerField = $GLOBALS['TCA'][$table]['ctrl']['label'];
         // Getting "copy-after" fields if applicable:
         $copyAfterFields = $destPid < 0 ? $this->fixCopyAfterDuplFields($table, $uid, abs($destPid), false) : [];