Rollup merge of #32923 - jseyfried:fix_hygiene, r=nrc

Fix macro hygiene bug

This fixes #32922 (EDIT: and fixes #31856), macro hygiene bugs.
It is a [breaking-change]. For example, the following would break:
```rust
fn main() {
    let x = true;
    macro_rules! foo { () => {
        let x = 0;
        macro_rules! bar { () => {x} }
        let _: bool = bar!();
        //^ `bar!()` used to resolve the first `x` (a bool),
        //| but will now resolve to the second x (an i32).
    }}
    foo! {};
}
```

r? @nrc

0 files changed, 0 insertions, 0 deletions