Breaking: #72666 - RTE: Remove relative path calculations

See forge#72666

Description

Since the removal of the feature editing static files with the Rich Text Editor (option "static_file_edit"), the path calculations for files within the HtmlParser including the method RteHtmlParser->setRelPath() have been removed as well.

Impact

Using the method RteHtmlParser->setRelPath() will result in a fatal PHP error.

Affected Installations

Any installations with custom RTE transformations that use a custom implementation of the RteHtmlParser PHP class.