Betting that a reference to “terms of service” on the sign-up page of its wagering app was “the virtual equivalent of a staple,” Caesars Sportsbook argued Cassandra Geske was obligated to arbitrate her claim that it violated consumer protection laws when it promised “risk-free” wagers for new customers.The top of the page said, in all caps, “terms and conditions.” And the first of five bullet-point items — after the statement, “By submitting, I confirm that:” — was “I agree to the Terms of Service.” At the bottom of the …