[TASK] Allow installation of guzzlehttp/psr7 v3

[bnf]

In order to prepare for guzzlehttp/guzzle v8 in
TYPO3 core, we allow the installation of the
guzzlehttp/psr7 helper package.

composer req guzzlehttp/psr7:"^2.5.0 || ^3.0"

Releases: main, 9, 8

[sbuerk]

Hey @bnf , do we really need to go down to 6 ?

In general 6 & 7 is not really considered maintained anymore and there could be now a some issue (regarding pipelines) and similar. Not that I'm trying to block that, but we should talk about that because I need to ensure that everything works pipeline wise so I can do than all the releases.

I checked the composer.json down to 6 for the current require constraint and tried to elaborate what would be the constraint to set for each version (backport wise).

Can you check and confirm it ?

branch	current	new (suggested)
main	^2.5.0	^2.5.0 || ^3.0
9	^2.5.0	^2.5.0 || ^3.0
8	^2.5.0	^2.5.0 || ^3.0
7	^2.5.0	^2.5.0 || ^3.0
6	^1.7 || ^2.0	^1.7 || ^2.5.0 || ^3.0

From what I checked on packagist.org so far that should be doable / safe.

[bnf]

Hey @sbuerk, let's go with 9 and 8 for now.
I'll evaluate if we need v7 and v6 as well. Thanks!