Muhammara: NULL pointer dereference in LZWDecode filter when DecodeParms omits EarlyChange key

Muhammara is a node module with c/cpp bindings to modify PDF with JavaScript for node or electron. Prior to 6.0.5, Muhammara PDFParser::CreateFilterForStream() in src/deps/PDFWriter/PDFParser.cpp dereferences a null PDFInteger pointer when a PDF stream uses the LZWDecode filter with a DecodeParms dictionary that omits the EarlyChange key. An application that processes an untrusted PDF and reads the affected stream can crash, causing a denial of service. This issue is fixed in version 6.0.5.