Update `std::rank` reference

[Rageking8]

• Convert "Class" to lowercase, use "Template parameters" heading, rename Ty template parameter to Type
• Expand the example with decltype use case
• Add backticks, clean up superfluous relative links, and update metadata

[learn-build-service-prod[bot]]

Learn Build status updates of commit 344fa16:

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File	Status	Preview URL	Details
docs/standard-library/rank-class.md	:white_check_mark:Succeeded

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[prmerger-automator[bot]]

PRMerger Results

Issue	Description
File Change Percent	This PR contains file(s) with more than 30% file change.

[v-dirichards]

@TylerMSFT

Can you review the proposed changes?

Important: When the changes are ready for publication, adding a #sign-off comment is the best way to signal that the PR is ready for the review team to merge.

#label:"aq-pr-triaged" @MicrosoftDocs/public-repo-pr-review-team

[TylerMSFT]

#sign-off