fix(adding_lints): usage of early vs late lint pass

[aaron-ang]

changelog: none

This PR fixes explaining the difference in usage between early and late lint passes in the book.

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[aaron-ang]

@y21 I have updated the paragraph.

[Alexendoo]

This still seems to flip the meaning, if only AST information is needed we'd still prefer it to be a late lint pass

[aaron-ang]

My understanding is that EarlyLintPass is a subset of LateLintPass. In what cases should we use EarlyLintPass, then? When editing this paragraph, I considered the context in which it is written. The author uses an example of an EarlyLintPass and explains that "we only have to deal with the AST and don't have to deal with the type system at all."

If this edit still seems to flip the meaning, we should consider editing other parts of the section.

[flip1995]

I think the new formulation is correct. Why would we prefer a LateLintPass if only AST information are required?

[Alexendoo]

what cases should we use EarlyLintPass, then?

It's not a strict subset, there's occasionally information that is present in the AST but not in the HIR. IIRC some information about use declarations aren't preserved in the HIR for example

Why would we prefer a LateLintPass if only AST information are required?

Because when either a late or early pass would work there's no advantage to going with an early pass, yet lints often find themselves needing type information further down the line. Types aside many util functions are written for late passes

[flip1995]

LGTM