MotionMark's multiply suite may generate incorrect score when requestAnimationFrame runs at 120hz

https://bugs.webkit.org/show_bug.cgi?id=240605

Reviewed by Simon Fraser.

This effectively increases the maximum complexity. Doing this for
two reasons: both Chrome and Safari are getting close to the maximum
complexity. Increasing the complexity ensures Chrome is scored
correctly when requestAnimationFrame runs at 120Hz.

Merge from https://commits.webkit.org/251810@main

* PerformanceTests/MotionMark/tests/master/resources/multiply.js:
Increases complexity.