Upgrade to use psr/http-message v2.0

[aedart]

Description

During athenaeum v8.0.0, psr/http-message version ^1.1 || ^2.0 was set as a dependency. This sadly introduced a defect, because the \Aedart\Streams\Stream component didn't specify the correct return types (_see #187 _).

Possible solution

psr/http-message version 2.0 cannot be used in the version 8-series, without introducing a breaking change. But, from version 9, this dependency MUST be upgraded.

Additional Context

The following 3rd party packages rely on version 1.0 of the Psr http-message package. These will have to be upgraded, before Athenaeum can be upgraded as well.

ramsey/http-range 1.1.0    requires psr/http-message (^1.0)         
shrikeh/teapot    v2.3.1   requires psr/http-message (^1.0)    

[aedart]

See ramsey/http-range#9