Fix compiler warning for examples/demo.rs (unnecessary parentheses)

Author: LinusCDE

examples/demo.rs

@@ -535,7 +535,7 @@ fn on_wacom_input(app: &mut appctx::ApplicationContext<'_>, input: input::WacomE
                 ];
                 let radii: Vec<f32> = points
                     .iter()
-                    .map(|point| ((mult as f32 * (point.1 as f32) / 2048.) / 2.0))
+                    .map(|point| (mult as f32 * (point.1 as f32) / 2048.) / 2.0)
                     .collect();
                 // calculate control points
                 let start_point = points[2].0.midpoint(points[1].0);