Apply suggestion from @Urgau

shorthand is always `crate`, `self`, or `super`.

Co-authored-by: Urgau <3616612+Urgau@users.noreply.github.com>

Author: CoCo-Japan-pan

compiler/rustc_ast_pretty/src/pprust/state/item.rs

@@ -489,7 +489,7 @@ impl<'a> State<'a> {
         match &impl_restriction.kind {
             ast::RestrictionKind::Restricted { path, shorthand, .. } => {
                 let path = Self::to_string(|s| s.print_path(path, false, 0));
-                if *shorthand && (path == "crate" || path == "self" || path == "super") {
+                if *shorthand {
                     self.word_nbsp(format!("impl({path})"))
                 } else {
                     self.word_nbsp(format!("impl(in {path})"))