[!!!][TASK] Remove obsolete RteHtmlParser logic and methods

Removed:
- RteHtmlParser->siteUrl()
- RteHtmlParser->getUrl()
- RteHtmlParser->HTMLcleaner_db() second parameter unused
- RteHtmlParser->getKeepTags() second parameter unused

Resolves: #72686
Releases: master
Change-Id: I0c4b4b6d17e3310218f9affc6d46418c1722ab68
Reviewed-on: https://review.typo3.org/45870


Reviewed-by: Andreas Fernandez <typo3@scripting-base.de>
Tested-by: Andreas Fernandez <typo3@scripting-base.de>
Reviewed-by: Wouter Wolters <typo3@wouterwolters.nl>
Tested-by: Wouter Wolters <typo3@wouterwolters.nl>