`match_single_binding` suggestion potentially produces different behavior

Summary

The suggestion currently puts the bindings outside of the block, which can extend their lifetimes and potentially shadow other values.

Reproducer

I tried this code:

let foo = 3;
match (1, 2) {
    (foo, bar) => {
        println!("{}", foo + bar); // 3
    }
}

println!("{}", foo + 3); // 6

I expected to see this happen:

let foo = 3;
{
    let (foo, bar) = (1, 2);
    println!("{}", foo + bar); // 3
}

println!("{}", foo + 3); // 6

Instead, this happened:

let foo = 3;
let (foo, bar) = (1, 2);
{
    println!("{}", foo + bar); // 3
}

println!("{}", foo + 3); // 4

Version

rustc 1.62.0-nightly (8f36334ca 2022-04-06)
binary: rustc
commit-hash: 8f36334ca939a67cce3f37f24953ff6f2d3f3d33
commit-date: 2022-04-06
host: x86_64-unknown-linux-gnu
release: 1.62.0-nightly
LLVM version: 14.0.0

Additional Labels

@rustbot label +C-enhancement

Start by locating the match_single_binding lint and reproduce the issue with the Rust example in the report. Compare the generated suggestion with the expected block-scoped form; done means the suggestion preserves the outer foo value and produces the expected behavior.