test：migrate doc/directory/docscrape to snapbox

[heisen-li]

What does this PR try to resolve?

Complete the following file migration:

 tests/testsuite/directory.rs
 tests/testsuite/doc.rs
 tests/testsuite/docscrape.rs

part of #14039

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[weihanglo]

Could you reorder commits 8ac39ec? That should happen before any other commits otherwise the redaction doesn't make sense.

[heisen-li]

Could you reorder commits 8ac39ec? That should happen before any other commits otherwise the redaction doesn't make sense.

OK，thanks.opening redact it only happens in the doc.rs file, so I adjusted the order of the two commits.

[weihanglo]

Thanks!

@bors r+

[bors]

📌 Commit e29862c has been approved by weihanglo

It is now in the queue for this repository.

[bors]

⌛ Testing commit e29862c with merge a0b2803...

[bors]

☀️ Test successful - checks-actions
Approved by: weihanglo
Pushing a0b2803 to master...