libreoffice/htmlfuzzer: Bad-cast to SwTableBox from SwClient in DelBoxNode

Project: git://anongit.freedesktop.org/libreoffice/core Detailed report: https://oss-fuzz.com/testcase?key=4979545733070848 Project: libreoffice Fuzzer: libFuzzerlibreofficehtmlfuzzer Fuzz target binary: htmlfuzzer Job Type: libfuzzerubsanlibreoffice Platform Id: linux Crash Type: Bad-cast Crash...