Breaking: #61823 - Remove magic setter for $fromTC 

See forge#61823

Description 

The magic setter for $fromTC in TYPO3CMSCoreDatabaseRelationHandler is removed.

Impact 

Directly setting the protected property $fromTC will trigger a PHP warning.

Affected installations 

Any installation using an extension that sets $fromTC property directly.

Migration 

Use \TYPO3\CMS\Core\Database\RelationHandler::setFetchAllFields() instead.