No longer suggests `&[i32]` or `&mut [i32]` instead of `&Vec<i32>` or
`&mut Vec<i32>` (also: `Path` and `PathBuf`, etc.) for the parameter
type when the parameter name starts with an underscore (or, if that does
not start with one, then a local `let` binding in the function body,
pointing to the same value, does) – (Fixesrust-lang/rust-clippy#13489,
fixesrust-lang/rust-clippy#13728)
~changelog: fix false positive: [`ptr_arg`] no longer triggers with
underscore binding to `&mut` argument~
changelog: fix false positive: [`ptr_arg`] no longer triggers with
underscore binding to `&T` or `&mut T` argument
*Edit:* This change has been extended to all references, not just
mutable ones. See [discussion below](#issuecomment-3006386877).