Unable to decode bundle

Hey,

When simulating a `bundle`, everything works just fine, however, when submitting it using:

```js
const bundleReceipt = await flashbotsProvider.sendRawBundle(
signedBundle,
targetBlockNumber
);
```

Then I get the following error message:

`{ error: { message: 'unable to decode bundle', code: -32000 } }`

> I instantiate my `flashbotsProvider` as follows:

```js
const flashbotsProvider = await FlashbotsBundleProvider.create(
await alchemy.config.getProvider(),
new Wallet(process.env.SIGNER_PRIVATE_KEY, alchemy)
);
```

Any thoughts?