Cynthia Erivo trusted her instincts and leapt into action to defend her co-star Ariana Grande last week — and now she’s opening up about the experience. Last Thursday, during the “Wicked: For Good” premiere in Singapore , a man vaulted over a barrier to accost Grande. A video of the incident showed Erivo immediately turning toward the singer to shield her as he rushed at them. “We have come through some shit,” Erivo said during a Saturday screening of the film in Los Angeles. “We have come