Async Await Support
sloth-pipe supports asynchronous operations within the pipeline. Functions passed to to or tap
can be asynchronous, and exec will return a Promise if any function in the pipeline is
asynchronous.
Async Example:
const asyncResult = await Pipe(5)    .to(async (x) => x * 2)    .to(async (x) => x + 3)    .exec();
console.log(asyncResult); // Outputs: 13