Tweak Debug representation of custom tokens

For example given:

    custom_keyword!(interface);
    custom_punctuation!(Spaceship, <=>);

    struct Demo {
        keyword: Token![struct],
        punct: Token![=>],
        custom_keyword: kw::interface,
        custom_punct: Spaceship,
    }

The Debug would be:

    Demo {
        keyword: Struct,
        punct: FatArrow,
        custom_keyword: Keyword [interface],
        custom_punct: Spaceship,
    }
diff --git a/src/custom_punctuation.rs b/src/custom_punctuation.rs
index 72ce21d..a05e18c 100644
--- a/src/custom_punctuation.rs
+++ b/src/custom_punctuation.rs
@@ -188,12 +188,12 @@
 // Not public API.
 #[cfg(feature = "extra-traits")]
 #[doc(hidden)]
-#[macro_export(local_inner_macros)]
+#[macro_export]
 macro_rules! impl_extra_traits_for_custom_punctuation {
     ($ident:ident, $($tt:tt)+) => {
         impl $crate::export::Debug for $ident {
             fn fmt(&self, f: &mut $crate::export::Formatter) -> $crate::export::fmt::Result {
-                $crate::export::Formatter::write_str(f, stringify_punct!($($tt)+))
+                $crate::export::Formatter::write_str(f, stringify!($ident))
             }
         }