Bump min php version to 8.0

[colemanw]

Overview

With the major version bump to Civi 6.0, let's also bump the dependencies.
PHP 7.4 has been EOL since 2022, time to drop it.

Technical Details

Note that existing sites that use php 7.4 won't immediately stop working, rather a system check will alert them "To ensure the continued operation of CiviCRM, upgrade your server now."

This required a minor version bump to typo3/phar-stream-wrapper, which seems fine.

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[seamuslee001]

@colemanw Eileen already had a PR for this here #31652

[colemanw]

Well mine updates composer.lock

[colemanw]

@totten I think this is ready to go. Only failing tests are the ones from infra running php 7.4. I think all we need to do is bump that up.

[seamuslee001]

yeh and the WP / Drupal tests won't be fixed until we merge the relevant PRs in their repos