Credit the connection as well when streaming.

[abizjak]

Purpose

This fixes the issue for streaming calls

See

• Issue with waitStream connection window updates  haskell-grpc-native/http2-client#74
• waitReply and rawUnary credit the connection haskell-grpc-native/http2-grpc-haskell#46
• Make waitStream update connection flow control window. haskell-grpc-native/http2-client#75

For previous fixes for non-streaming calls.

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.