removed not needed namespaces

src/validation/rules/fields_on_correct_type.rs

@@ -40,7 +40,7 @@ impl<'a> Visitor<'a> for FieldsOnCorrectType {
                                 .iter()
                                 .map(|fields| fields.keys())
                                 .flatten()
-                                .map(std::string::String::as_str),
+                                .map(String::as_str),
                             &field.node.name.node,
                         )
                         .unwrap_or_default()

src/validation/rules/no_undefined_variables.rs

@@ -80,7 +80,7 @@ impl<'a> Visitor<'a> for NoUndefinedVariables<'a> {
         name: Option<&'a Name>,
         operation_definition: &'a Positioned<OperationDefinition>,
     ) {
-        let name = name.map(async_graphql_value::Name::as_str);
+        let name = name.map(Name::as_str);
         self.current_scope = Some(Scope::Operation(name));
         self.defined_variables
             .insert(name, (operation_definition.pos, HashSet::new()));