readFile is not exported by polyfill-node.fs.js

WHAT!!!!!!!!!

https://github.com/ErrorBot1122/Roblox-File-Handler/commit/d0670bd3bdb340588eef969ca6b85417a73351c3

my live code is on [replit](https://replit.com/@ErrorbotTHE2nd/Roblox-File-Handler-1#rollup.config.js)

**output:**
```
>> npm run test

> rbx-file-handler@0.0.0 test /home/runner/Roblox-File-Handler-1
> npm run build; mocha || true

> rbx-file-handler@0.0.0 build
> rollup --config

index.js → builds/robloxFileHandler.mjs, builds/robloxFileHandler.js, builds/robloxFileHandler.min.mjs, builds/robloxFileHandler.min.js...
(!) Unresolved dependencies
https://rollupjs.org/guide/en/#warning-treating-module-as-external-dependency
xml2js (imported by index.js)
(!) Missing exports
https://rollupjs.org/guide/en/#error-name-is-not-exported-by-module
index.js
readFile is not exported by polyfill-node.fs.js
348:
349: // Read the file
350: fs.readFile(path, (rErr, data) => {
^
351:
352: if (rErr) {
created builds/robloxFileHandler.mjs, builds/robloxFileHandler.js, builds/robloxFileHandler.min.mjs, builds/robloxFileHandler.min.js in 6.7s

Classes/*.mjs, Datatypes/*.mjs, Enums/*.mjs → builds/RoModules.mjs, builds/RoModules.min.mjs...
created builds/RoModules.mjs, builds/RoModules.min.mjs in 2.8s

MAIN
parseFile
✔ Exists?
✔ Returns object with valid XML? (64ms)
Read any valid RBXLX file
✔ Can parse simple baseplate? (RBXLX)
✔ Can parse simple baseplate? (XML) (97ms)
✔ Can parse simple baseplate? (TXT)
Read diffent file sizes
✔ Can parse a large normel RBXLX file (1211ms)
Classes
✔ exported classes exsit
✔ can create instance

BUILDS
✔ Normal build exists
✔ Minifided build exists
✔ Minifided build is smaller the normal build

11 passing (2s)
```

P.S. Sorry about the low quality, I'm just burned out today :(

polyfill-node.fs.js にあるエクスポート不足の警告から始め、リンク先プロジェクトの index.js と rollup.config.js を使ってビルドを再現します。readFile の既存の使用箇所とエクスポートを確認し、その後、報告されている npm test のフローを実行します。ビルドで readFile が不足していると報告されなくなり、テストも引き続きパスすれば完了です。

索引モデルが issue の本文から書いたものです。