[BUGFIX] Remove maxitems constraint from be_groups.pagetypes_select

The field be_groups.pagetypes_select is of type TEXT, which can contain
data of a maximum of 64 kilobytes. This patch removes the maxitems
constraint pinned to 20 items as a page type identifier usually is a few
bytes long.

Resolves: #93728
Releases: master, 10.4
Change-Id: I88ea4bb84eb054b22ed00e30f0a95dd4cd1e7375
Reviewed-on: https://review.typo3.org/c/Packages/TYPO3.CMS/+/68373


Tested-by: TYPO3com <noreply@typo3.com>
Tested-by: core-ci <typo3@b13.com>
Tested-by: Anja Leichsenring <aleichsenring@ab-softlab.de>
Tested-by: Guido Schmechel <guido.schmechel@brandung.de>
Tested-by: Oliver Bartsch <bo@cedev.de>
Tested-by: Christian Kuhn <lolli@schwarzbu.ch>
Reviewed-by: Anja Leichsenring <aleichsenring@ab-softlab.de>
Reviewed-by: Guido Schmechel <guido.schmechel@brandung.de>
Reviewed-by: Oliver Bartsch <bo@cedev.de>
Reviewed-by: Christian Kuhn <lolli@schwarzbu.ch>

typo3/sysext/core/Configuration/TCA/be_groups.php

@@ -121,7 +121,6 @@ return [
                 ],
             ]
         ],
-
         'pagetypes_select' => [
             'label' => 'LLL:EXT:core/Resources/Private/Language/locallang_tca.xlf:be_groups.pagetypes_select',
             'config' => [
@@ -130,7 +129,6 @@ return [
                 'special' => 'pagetypes',
                 'size' => 5,
                 'autoSizeMax' => 50,
-                'maxitems' => 20,
             ]
         ],
         'tables_modify' => [