add benchmark tests for async iterable list fields

benchmark/list-asyncIterable-benchmark.js

@@ -0,0 +1,24 @@
+import { execute } from 'graphql/execution/execute.js';
+import { parse } from 'graphql/language/parser.js';
+import { buildSchema } from 'graphql/utilities/buildASTSchema.js';
+
+const schema = buildSchema('type Query { listField: [String] }');
+const document = parse('{ listField }');
+
+async function* listField() {
+  for (let index = 0; index < 1000; index++) {
+    yield index;
+  }
+}
+
+export const benchmark = {
+  name: 'Execute Async Iterable List Field',
+  count: 10,
+  async measure() {
+    await execute({
+      schema,
+      document,
+      rootValue: { listField },
+    });
+  },
+};