Skip `unused_parens` report for `Paren(Path(..))` in macro.
fixes#120642
In following code, `unused_parens` suggest change `<($($rest),*)>::bar()` to `<$rest>::bar()` which will cause another err: `error: variable 'rest' is still repeating at this depth`：
```rust
trait Foo {
fn bar();
}
macro_rules! problem {
($ty:ident) => {
impl<$ty: Foo> Foo for ($ty,) {
fn bar() { <$ty>::bar() }
}
};
($ty:ident $(, $rest:ident)*) => {
impl<$ty: Foo, $($rest: Foo),*> Foo for ($ty, $($rest),*) {
fn bar() {
<$ty>::bar();
<($($rest),*)>::bar()
}
}
problem!($($rest),*);
}
}
```
I think maybe we can handle this by avoid warning for `Paren(Path(..))` in the macro. Is this reasonable approach?
82c6f187ad