tokenizer: fixed handling of empty numeric entities
tokenizer: fixed handling of empty numeric entities

eg. &#x;

frontapp/htmlparser2,mail-apps/htmlparser2,broadly/htmlparser2,jasonsanjose/htmlparser2,jasonsanjose/htmlparser2,fasterize/node-htmlparser,magicode/htmlparser2,broadly/htmlparser2,magicode/htmlparser2,frontapp/htmlparser2,mail-apps/htmlparser2