[TASK] Increase length of header_position field

To prevent the truncation of new values via TCEForm,
the field length is increased to 255.

Resolves: #88722
Releases: master, 9.5
Change-Id: I982c20302be216c1819da9efc468f8a7b2be0add
Reviewed-on: https://review.typo3.org/c/Packages/TYPO3.CMS/+/61283


Tested-by: TYPO3com <noreply@typo3.com>
Tested-by: Daniel Goerz <daniel.goerz@posteo.de>
Tested-by: Riccardo De Contardi <erredeco@gmail.com>
Tested-by: Tymoteusz Motylewski <t.motylewski@gmail.com>
Reviewed-by: Oliver Klee <typo3-coding@oliverklee.de>
Reviewed-by: Björn Jacob <bjoern.jacob@tritum.de>
Reviewed-by: Daniel Goerz <daniel.goerz@posteo.de>
Reviewed-by: Riccardo De Contardi <erredeco@gmail.com>
Reviewed-by: Tymoteusz Motylewski <t.motylewski@gmail.com>

typo3/sysext/frontend/ext_tables.sql

@@ -95,7 +95,7 @@ CREATE TABLE sys_template (
 CREATE TABLE tt_content (
 	CType varchar(255) DEFAULT '' NOT NULL,
 	header varchar(255) DEFAULT '' NOT NULL,
-	header_position varchar(6) DEFAULT '' NOT NULL,
+	header_position varchar(255) DEFAULT '' NOT NULL,
 	rowDescription text,
 	bodytext mediumtext,
 	bullets_type tinyint(3) unsigned DEFAULT '0' NOT NULL,