Make the `dangerous_implicit_autorefs` lint deny-by-default I intended for the `dangerous_implicit_autorefs` lint to be deny-by-default, the [T-lang nomination comment](https://github.com/rust-lang/rust/pull/123239#issuecomment-2727551097) even clearly mentioned deny-by-default, but somehow I and other missed that it is only warn-by-default. I think the lint should still be deny-by-default as the implicit aliasing requirements can be quite dangerous. In any-case, opening this PR for T-lang awareness. `@rustbot` label +I-lang-nominated +T-lang r? `@traviscross`