Follow-up from "[TASK] Use Environment API instead of PATH_site"

The following discussion from !557 (merged) should be addressed:

• @tomalo.stuttgart started a discussion: (+2 comments)

              GeneralUtility::getURL(Environment::getPublicPath() . '/' . $GLOBALS['TYPO3_CONF_VARS']['BE']['fileadminDir'] . 'currentcoredata.json'),