[bugfix] Ensure pre renders as expected, fix orderedCollectionPage

[tsmethurst]

Description

If this is a code change, please include a summary of what you've coded, and link to the issue(s) it closes/implements.

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This PR fixes styling for pre code blocks on the web so that they render properly again.

Also adds a new status to the testrig for zork so that we can more easily test styling of big pre blocks.

While adding a new status, also uncovered a bug in our AP serialization where we weren't serializing orderedItems properly on orderedCollectionPages, so fixes that too!

Checklist

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• I/we have read the GoToSocial contribution guidelines.
• I/we have discussed the proposed changes already, either in an issue on the repository, or in the Matrix chat.
• I/we have performed a self-review of added code.
• I/we have written code that is legible and maintainable by others.
• I/we have commented the added code, particularly in hard-to-understand areas.
• I/we have made any necessary changes to documentation.
• I/we have added tests that cover new code.
• I/we have run tests and they pass locally with the changes.
• I/we have run go fmt ./... and golangci-lint run.