Make creating AllAstNodeIter explicit.

This is to remove the ambiguity between calling iter on the specific structs like Document and calling iter on an AstNode by having an explicitly-named function to create the iterator.

src/parser/document.rs

@@ -143,7 +143,7 @@ fn document_org_source<'b, 'g, 'r, 's>(
     {
         // If there are radio targets in this document then we need to parse the entire document again with the knowledge of the radio targets.
         let all_radio_targets: Vec<&Vec<Object<'_>>> = Into::<AstNode>::into(&document)
-            .into_iter()
+            .iter_all_ast_nodes()
             .filter_map(|ast_node| {
                 if let AstNode::RadioTarget(ast_node) = ast_node {
                     Some(ast_node)