Page Six may be compensated and/or receive an affiliate commission if you click or buy through our links. Featured pricing is subject to change. As Page Six’s Associate Shopping Editor, I’ve tried plenty of mascaras over the years — but only one has become my absolute must-have. While I used to be skeptical of an over-$20 mascara, since testing out YSL Lash Clash, I haven’t turned back. And since the one thing I don’t like about it is the price tag, year after year I stock up by buying a discounted duo during the Nordstrom Anniversary Sale. Since YSL products hardly ever get marked down, it’s truly the golden opportunity to try them for…