Rollup merge of #138577 - aDotInTheVoid:deprecate-deprecations, r=GuillaumeGomez

rustdoc-json: Don't also include `#[deprecated]` in `Item::attrs`

Closes #138378

Not sure if this should bump `FORMAT_VERSION` or not. CC `@Enselic` `@LukeMathWalker` `@obi1kenobi`

r? `@GuillaumeGomez,` best reviewed commit-by-commit

Author: matthiaskrgr