For some odd reason, the function "isNaN" no longer works in GameTest scripts as of 1.17.40. It always returns false, even the value passed in is `NaN`.

Steps to Reproduce:

1. Make a behaviour pack with a Gametest script that does the followings (Updated for 1.18.10):

   world.getDimension('overworld').runCommand(`say ${isNaN(NaN)}`);

1. Import the pack to a world (Gametest framework enabled) and run it.

  
Observed Results:

Chat says

false

Expected Results:

Chat should say

true

Notes:

Fortunately this can worked around by comparing the value to itself, but it would be great if a common function such as this works as intended.