Auto merge of #47767 - estebank:as-suggestion, r=petrochenkov

Correctly format `extern crate` conflict resolution help

Closes #45799. Follow up to @Cldfire's #45820.

If the `extern` statement that will have a suggestion ends on a `;`, synthesize a new span that doesn't include it.

src/libsyntax/parse/parser.rs

@@ -6115,6 +6115,7 @@ impl<'a> Parser<'a> {
         self.expect(&token::Semi)?;
 
         let prev_span = self.prev_span;
+
         Ok(self.mk_item(lo.to(prev_span),
                         ident,
                         ItemKind::ExternCrate(maybe_path),