Released reactphp/promise-stream v1.6.0

[SimonFrings]

Released reactphp/promise-stream v1.6.0 today 🎉

• Feature: Update unwrapped stream to avoid unhandled promise rejections.
  (#37 by @clue)

• Feature: Improve first() promise resolution to clean up any garbage references.
  (#36 by @lucasnetau)

• Improve test suite and project setup and report failed assertions.
  (#34 by @clue and #35 by @WyriHaximus)

– See https://github.com/reactphp/promise-stream/releases/tag/v1.6.0