Feature request: Infinity timeout

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In the current version, although Infinity is a valid value to the milliseconds parameter,

typeof Infinity === 'number' && Infinity > 0 // true

it actually times out immediately both in browsers and Nodejs environment (tested on Chrome 76.0.3809.132 and Node v12.7.0).

You can take a look at the following snippet.

setTimeout(() => console.log("Infinity timeout"), Infinity);
setTimeout(() => console.log("Immediate timeout"));

// Infinity timeout
// Immediate timeout

Nodejs also output the following message.

(node:19336) TimeoutOverflowWarning: Infinity does not fit into a 32-bit signed integer.
Timeout duration was set to 1.

I understand that it is meaningless to use setTimeout with Infinity timeout, since the callback will never invoked if setTimeout is implemented with really "infinity" timeout.

But as p-timeout, it's a timer waiting for a promise to be resolved, and thus we expected the infinity timeout for p-timeout means that no matter how long it takes to resolve the promise, we will wait.

So I suggest if the milliseconds is Infinity, simply fallback to original promise without timer wrapped, then the behavior is as expected.