Feature: #69730 - Introduce uniqueId generator

See Issue #69730

Description

A new method getUniqueId() has been added to the StringUtility class. Now there is a common way to generate an unique identifier which can be used even in HTML tag attributes as it removes the invalid dot character.

$uniqueId = \TYPO3\CMS\Core\Utility\StringUtility::getUniqueId('Prefix');

Impact

No need to remove the dot manually anymore.