chore: Testing with WordPress 6.8

[colinmurphy]

Description

WordPress 6.8 was released yesterday - https://wordpress.org/news/2025/04/cecil/

We need to test and ensure WPGraphQL Content Blocks works with WordPress 6.8 and update the test suite and other related information for WPGraphQL Content Blocks (e.g. tested until)

[colinmurphy]

@justlevine FYI

[justlevine]

Thanks @colinmurphy . We're tackling this in rtCamp/snapwp-helper#109 , and while we're not testing Content Blocks explicitly, the only issues we're seeing look like they're related to our test setup and not WPGraphQL Content Blocks, so hopefully there isn't much compat work needed 🤞

[colinmurphy]

Thanks @justlevine 🚀

We will be testing this either today or tomorrow and getting any tests updated etc (assuming there is no issues).

[colinmurphy]

@justlevine

Created a PR here - #369

I couldn't find any obvious issues when testing 6.8 and just checking in if you found anything.