Stealth code randomizes hardwareConcurrency and deviceMemory on every access

[TheTechRobo]

I was surprised to learn how brozzler's stealth JavaScript handles deviceMemory and hardwareConcurrency:

brozzler/brozzler/js-templates/stealth.js

Lines 30 to 35 in a665d49

	Object.defineProperty(navigator, 'deviceMemory', {
	get: () => getRandomInt(4, 32)
	});
	Object.defineProperty(navigator, 'hardwareConcurrency', {
	get: () => getRandomInt(4, 32)
	});

Every call to either property returns a random value, so even simply [navigator.hardwareConcurrency, navigator.hardwareConcurrency] will have two different values in the array. Why is this? Why not pick a random number at the start and use that one? (Or even pick a common constant value like 4 or 8 so it's the same across page loads.)