test: use createReadStream instead of ReadStream

This commit updates test-fs-read-stream to use fs.createReadStream
instead of using fs.ReadStream. All other places in this test use
the former.

PR-URL: https://github.com/nodejs/node/pull/19636


Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>
Reviewed-By: Trivikram Kamat <trivikr.dev@gmail.com>
Reviewed-By: Weijia Wang <starkwang@126.com>
Reviewed-By: James M Snell <jasnell@gmail.com>