fix: Fix unwrap_branch in match_arm

[A4-Tacks]

Example

fn main() {
    match 1 {
        1 => if true {
            foo();
        } else {$0
            bar();
        }
        _ => (),
    }
}

Before this PR

fn main() {
    match 1 {
        1 => if true {
            foo();
        }
        bar();
        _ => (),
    }
}

After this PR

fn main() {
    match 1 {
        1 => {
            bar();
        }
        _ => (),
    }
}