v5 support

[ncla]

WIP

Problems found:

• Multisites config has been moved
• Glide now always outputs URLs with original filename https://github.com/statamic/cms/pull/9616
• Missing alt attribute string

Things to check:

• Glide hash https://github.com/statamic/cms/pull/9918
• https://github.com/statamic/cms/pull/9871
• https://github.com/statamic/cms/pull/9573

Things to check from v4:

• https://github.com/statamic/cms/pull/9378
• https://github.com/statamic/cms/pull/9109

v5.0 cms upgrade guide for reference: https://github.com/statamic/docs/pull/1311/files

Supported things would be the same as Statamic core package:

• PHP 8.1, 8.2, 8.3
• Laravel 10, 11
• Statamic 5

[riasvdv]

I've chosen to just get the tests passing for now, things like the improved TestCase is something we can add in the future