[BUGFIX] Declare guzzlehttp/psr7 dependency

guzzlehttp/psr7 is not only an indirect dependency
from guzzlehttp/guzzle, but also a direct core
dependency since we extend LazyOpenStream in
SelfEmittableLazyOpenStream. Declare that dependency
directly, which also blocks upcoming guzzlehttp/psr7:2.0
which is currently incompatible with our core use.

composer req guzzlehttp/psr7:^1.7.0
composer req guzzlehttp/psr7:^1.7.0 -d typo3/sysext/core --no-update

Change-Id: I4968bc854545262ce0230ea71647463f5a332f54
Resolves: #94422
Releases: master, 10.4, 9.5
Reviewed-on: https://review.typo3.org/c/Packages/TYPO3.CMS/+/69668


Tested-by: core-ci <typo3@b13.com>
Tested-by: Benni Mack <benni@typo3.org>
Tested-by: Oliver Bartsch <bo@cedev.de>
Tested-by: Christian Kuhn <lolli@schwarzbu.ch>
Reviewed-by: Benni Mack <benni@typo3.org>
Reviewed-by: Oliver Bartsch <bo@cedev.de>
Reviewed-by: Christian Kuhn <lolli@schwarzbu.ch>