Merge #6719

6719: Use items can also have doc comments r=matklad a=Veykril

Prior to this change modules show more docs than they have cause they inherit the docs from documented use items inside of them.

Co-authored-by: Lukas Wirth <lukastw97@gmail.com>

crates/syntax/src/ast/node_ext.rs

@@ -477,3 +477,4 @@ impl ast::DocCommentsOwner for ast::Const {}
 impl ast::DocCommentsOwner for ast::TypeAlias {}
 impl ast::DocCommentsOwner for ast::Impl {}
 impl ast::DocCommentsOwner for ast::MacroCall {}
+impl ast::DocCommentsOwner for ast::Use {}