este es mi backend index.js en AWS Lambda. Ya probé CORS de todas las formas que conocemos, pero aún no funciona. TT, ¿debo configurar algo en AWS primero?

 const { ApolloServer, gql } = require('apollo-server-lambda') const express = require('express'); const cors = require('cors'); const jwt = require('express-jwt'); const cookieParser = require('cookie-parser'); const schema = require('./graphql'); const mongoose = require('mongoose'); const path = "/graphql"; const server = new ApolloServer({ schema, context: ({ event, context }) => ({ headers: event.headers, functionName: context.functionName, event, context, }) }); exports.handler = server.createHandler({ expressGetMiddlewareOptions: { cors: { origin: "http://localhost:3000", credentials: true, } }, expressAppFromMiddleware(middleware) { const app = express(); const mongodb_uri = "mongodb+srv://###############################################" mongoose.Promise = Promise; mongoose.connect(mongodb_uri, { dbName: "myDB", promiseLibrary: Promise, useNewUrlParser: true, useUnifiedTopology: true, useCreateIndex: true, useFindAndModify: false, }); app.use(cookieParser()); app.use(express.json()); app.use(express.urlencoded({ extended: false })); app.use( cors({ origin: "http://localhost:3000", credentials: true, }) ); });

cuando llamo al backend desde http://localhost:3000 (frontend), obtenemos un error

 Access to fetch at 'https://####################################' from origin 'http://localhost:3000' has been blocked by CORS policy: Response to preflight request doesn't pass access control check: The value of the 'Access-Control-Allow-Origin' header in the response must not be the wildcard '*' when the request's credentials mode is 'include'. createHttpLink.ts:145 POST https://#################################### net::ERR_FAILED