Why does Romeo say shake the yoke of inauspicious stars?

In Shakespeare's play "Romeo and Juliet," Romeo does not say the phrase "shake the yoke of inauspicious stars." The line you might be referring to is "O, let's begone; my soul is full of discord and jealousy is the green-eyed monster, which doth mock the meat it feeds on. Let's begone and leave it behind for the devil."