fastify-mongodb: Mongodb connection error

Prerequisites

• I have written a descriptive issue title
• I have searched existing issues to ensure the bug has not already been reported

Fastify version

3.22.1

Plugin version

4.1.1

Node.js version

16.13.0

Operating system

Linux

Operating system version (i.e. 20.04, 11.3, 10)

20.04

Description

Hello. I launched a clustered mongodb and enabled authentication. But the fastify-mongodb plugin does not connect with authentication (AuthenticationFailed). But there is no problem with MongoClient.

Steps to Reproduce

const fastify = require("fastify");
const app = fastify();

app.register(require('fastify-multipart'))
app.register(require('fastify-formbody'))
app.register(require('./FastifyRouter'))

//database
app.register(require('fastify-mongodb'), {
    forceClose: true,
    url: 'mongodb://localhost:27017/db',
    auth: {
        username: "username",
        password: "password"
    }
})

app.listen(port,"hostname",(err,adrs) => {
    if (err) {
        console.log(err)
    } else {
        console.log(address)
    }
})

Expected Behavior

No response