Fix Reference::getTheirFieldName getter usage

[mvorisek]

fix #1853

@mkrecek234 please test

[mkrecek234]

@mvorisek The bug above seems fixed, ScopeBuilder however creates a new bug then with a boolean field (e.g., is_deleted) in this line of code:

ui/src/Form/Control/ScopeBuilder.php

Line 682 in 76755a8

'option' => static::getOption($inputType, $value, $condition),

throwing:

:: = {Atk4\Ui\Form\Control\ScopeBuilder}
$condition = {Atk4\Data\Model\Scope\Condition}
$inputType = "text"
$inputsMap = {string[78]} ["number", "number", "number", "date", "date", +73 more]
$operator = "equals"
$operatorKey = "equals"
$operatorsMap = {string[18]} ["=", "!=", ">", ">=", "<", +13 more]
$rule = "is_deleted"
$value = false
$_COOKIE = {string[1]} ["1eqggjdoafr1hg2..."]
$_SERVER = {array[32]}
$GLOBALS = {array[13]}

[mvorisek]

@mvorisek The bug above seems fixed, ScopeBuilder however creates a new bug then with a boolean field (e.g., is_deleted) in this line of code...

I tried to reproduce with boolean field and hit another ScopeBuilder issue. I filed #1855 issue for it. Probably some issue with (no to ui) typecasting. But the exception is different than you posted here, so please post on the issue to reproduce the exception you get.

This PR fixes #1853 and I am merging it.