[BUGFIX] Use correct module name for checking permissions to help module

The correct module name is `help_cshmanual` to show editors additional
help information.

Resolves: #95431
Releases: master, 10.4
Change-Id: I4d2e3e7461c0fc7a0b1facb0d07a317d6d8e55a9
Reviewed-on: https://review.typo3.org/c/Packages/TYPO3.CMS/+/71450
Tested-by: Benjamin Franzke <bfr@qbus.de>
Tested-by: core-ci <typo3@b13.com>
Reviewed-by: Benjamin Franzke <bfr@qbus.de>

typo3/sysext/backend/Classes/Utility/BackendUtility.php

@@ -2203,7 +2203,7 @@ public static function helpTextArray($table, $field)
             }
             // If we have more information to show and access to the cshmanual
             if (($data['image_descr'] || $data['seeAlso'] || $data['details'] || $data['syntax'])
-                && static::getBackendUserAuthentication()->check('modules', 'help_CshmanualCshmanual')
+                && static::getBackendUserAuthentication()->check('modules', 'help_cshmanual')
             ) {
                 $output['moreInfo'] = true;
             }