Fix buffering of streaming calls by updating the dependency.

[abizjak]

Purpose

Fix delays in streaming calls due to uncredited connection window updates.

Depends on

• Credit the connection as well when streaming. http2-grpc-haskell#4

Fixes #213

Checklist

• My code follows the style of this project.
• The code compiles without warnings.
• I have performed a self-review of the changes.
• I have documented my code, in particular the intent of the
  hard-to-understand areas.
• (If necessary) I have updated the CHANGELOG.