Beyonce might wanna watch her back, cause Serena Williams is channeling her inner Queen Bey — and doing a pretty damn good job at it in a brand new video. Serena — the cover girl for April’s issue of Vogue — teamed up with the mag to take over the BallenIsles Country Club in Palm Beach for her own version of Beyonce’s “7/11” music video. Serena plays a little tennis, has a little fun, and even does a little twerking. Clap, clap, clap, clap …