Can polyfill references be removed?

When working on https://github.com/IronCoreLabs/ironweb/pull/97 I came across several references to polyfill as a fallback for cryptographic operations. I don't think these are probably needed anymore.

eg:

```javascript
return NativeAes.decryptDeviceAndSigningKeys(devicePrivateKey, signingPrivateKey, symmetricKey, iv).handleWith(() =>
PolyfillAes.decryptDeviceAndSigningKeys(devicePrivateKey, signingPrivateKey, symmetricKey, iv)
)
```

Maybe everything in the [PolyFilAes file](https://github.com/IronCoreLabs/ironweb/blob/2ea3cb13b39a01a5dd7250a35c9b06eaf5299cbf/src/frame/worker/crypto/aes/PolyfillAes.ts) can be removed? Maybe sjcl can be removed?