Hi,
this is just a question, not an issue.
Why do you require ringcentral/psr7 from https://github.com/ringcentral/psr7 and not guzzle/psr7 from https://github.com/guzzle/psr7 ?
I see ringcentral is a fork of guzzle, but it doesn't explain why, and what's changed.
Wouldn't guzzle be a better choice?