Use clone_from from hashbrown::{HashMap,HashSet}.

[adlerd]

This change updates the std hash collections to use hashbrown's clone_from, which was itself added in #70052. Deriving Clone does not add a clone_from impl and uses the trait default, which calls clone.

Fixes#28481

[rust-highfive]

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[Mark-Simulacrum]

@bors r+ rollup=never

[bors]

📌 Commit 7adeb71 has been approved by Mark-Simulacrum

[bors]

⌛ Testing commit 7adeb71 with merge 0f42d47...

[bors]

☀️ Test successful - checks-actions
Approved by: Mark-Simulacrum
Pushing 0f42d47 to master...