fix: inner attribute followed by outer attribute causing ICE

Author: EliseZeroTwo

compiler/rustc_ast/src/tokenstream.rs

@@ -221,12 +221,6 @@ impl AttrAnnotatedTokenStream {
                     for attr in &data.attrs {
                         match attr.style {
                             crate::AttrStyle::Outer => {
-                                assert!(
-                                    inner_attrs.len() == 0,
-                                    "Found outer attribute {:?} after inner attrs {:?}",
-                                    attr,
-                                    inner_attrs
-                                );
                                 outer_attrs.push(attr);
                             }
                             crate::AttrStyle::Inner => {