fix(docs): Remove use of deprecated root.flush() API (#1896)

Author: iwoplaza

apps/typegpu-docs/src/examples/simulation/slime-mold/index.ts

@@ -289,8 +289,6 @@ function frame(now: number) {
     .with(renderBindGroups[1 - currentTexture])
     .draw(3);
 
-  root['~unstable'].flush();
-
   currentTexture = 1 - currentTexture;
 
   requestAnimationFrame(frame);