Add cached crate mdbook-linkcheck

[huangjj27]

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Crate

crates.io: https://crates.io/crates/mdbook-linkcheck
repository: https://github.com/Michael-F-Bryan/mdbook-linkcheck

Motivation

I was translating the async book and publish it with my own ci using actions-rs. However, each time it builds, actions-rs re-install mdbook-linkcheck without cache, whick takes about 5 min to pass the CI. With this crate cached, the CI will be made less than 20s.