The highlight rectangle was not rotated, handle it similar to
PDFWriterImpl::drawStrikeoutChar().

Change-Id: I97a5b1fc05706729c58c92b90d6808629af8ca4c
Reviewed-on: https://gerrit.libreoffice.org/42180Reviewed-by: Miklos Vajna <vmiklos@collabora.co.uk>
Tested-by: Jenkins <ci@libreoffice.org>