Add compatibility for SMW 7

[JimmyvanDelft]

Fixes form submissions on SMW 7, where ServicesFactory::newTitleFactory() was removed.
Uses SMW’s cross-version MaintenanceFactory instead, preserving compatibility with both SMW 6 and 7 on MediaWiki 1.43.

Info: I had a customer recently updated to SMW 7.2 and now almost all (if not all) flexform submissions fail because:

[exception] [357eed6dd20871e3da2307d7] /Speciaal:FlexForm
Error: Call to undefined method SMW\Services\ServicesFactory::newTitleFactory()

#16 /var/www/html/includes/exception/MWExceptionRenderer.php(190): MediaWiki\Output\OutputPage->output()
#17 /var/www/html/includes/exception/MWExceptionRenderer.php(109): MWExceptionRenderer::reportHTML(Error)
#18 /var/www/html/includes/exception/MWExceptionHandler.php(135): MWExceptionRenderer::output(Error, int)
#19 /var/www/html/includes/exception/MWExceptionHandler.php(239): MWExceptionHandler::report(Error)
#20 /var/www/html/includes/MediaWikiEntryPoint.php(222): MWExceptionHandler::handleException(Error, string)
#21 /var/www/html/includes/actions/ActionEntryPoint.php(83): MediaWiki\MediaWikiEntryPoint->handleTopLevelError(Error)
#22 /var/www/html/includes/MediaWikiEntryPoint.php(206): MediaWiki\Actions\ActionEntryPoint->handleTopLevelError(Error)

[wgevaert]

looks good to me!

[JimmyvanDelft]

@Designburo Could you merge this at your earliest convenience?