Currently, if you use axios with async / await, you get a stack trace like this:

```
Request failed with status code 500
    at createError (/Users/rmenezes/code/seedfi/web/node_modules/axios/lib/core/createError.js:16:15)
    at settle (/Users/rmenezes/code/seedfi/web/node_modules/axios/lib/core/settle.js:17:12)
    at IncomingMessage.handleStreamEnd (/Users/rmenezes/code/seedfi/web/node_modules/axios/lib/adapters/http.js:237:11)
    at IncomingMessage.emit (events.js:208:15)
    at IncomingMessage.EventEmitter.emit (domain.js:471:20)
    at endReadableNT (_stream_readable.js:1154:12)
    at processTicksAndRejections (internal/process/task_queues.js:77:11
```

It doesn't show you much about *what* called Axios., which makes debugging quite difficult!

This is because `settle` calls `createError`:
https://github.com/axios/axios/blob/master/lib/core/settle.js#L12-L24

Which creates a new error with a brand new stack trace:
https://github.com/axios/axios/blob/master/lib/core/createError.js#L15-L18

Perhaps we can fix this by creating an error before the request goes out and stitching it to the new error's stack trace?
test/unit/adapters/http.js
} catch (err){
        console.warn('HTTP server error:', err);
      }
    }).listen(port, function (err) {
      err ? reject(err) : resolve(this);
    });
    server.keepAliveTimeout = keepAlive;
  });
}
const stopHTTPServer = async (server, timeout = 10000) => {
  if (server) {
    if (typeof server.closeAllConnections === 'function') {
      server.closeAllConnections();
    }
    await Promise.race([new Promise(resolve => server.close(resolve)), setTimeoutAsync(timeout)]);
  }
}
const handleFormData = (req) => {
  return new Promise((resolve, reject) => {
    const form = new formidable.IncomingForm();
    form.parse(req, (err, fields, files) => {
      if (err) {
        return reject(err);
      }
      resolve({fields, files});
    });
  });
}
function generateReadableStream(length = 1024 * 1024, chunkSize = 10 * 1024, sleep = 50) {
  return stream.Readable.from(async function* (){