Rollup merge of #145389 - GuillaumeGomez:unstable-search, r=fmease

[rustdoc] Revert "rustdoc search: prefer stable items in search results"

Reverts rust-lang/rust#141658 and reverts rust-lang/rust#145349.

Reopens rust-lang/rust#138067.

r? ```@fmease```

Author: Zalathar