[Bug]: when rejecting the `eth_getEncryptionPublicKey` JSON-RPC method it does not return 4001

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### Describe the bug

I wrote a rule for the API Spec Test that expects all the confirmations to reject with 4001 and this method fails.

### Expected behavior

When rejecting I should see the response:

```json
{
"id": 10,
"jsonrpc": "2.0",
"error": {
"code": 4001,
"message": "User rejected the request."
}
}
```

### Screenshots/Recordings


### Steps to reproduce

1. send a request to `eth_getEncryptionPublicKey`
2. hit reject
3. see the error below

### Error messages or log output

```json
{
"id": 10,
"jsonrpc": "2.0",
"error": {
"code": -32603,
"data": {
"originalError": {}
},
"message": "MetaMask EncryptionPublicKey: User denied message EncryptionPublicKey."
}
}
```

### Version

sj/api-spec-tests

### Build type

Other (please specify exactly where you obtained this build in "Additional Context" section)

### Browser

Chrome

### Operating system

MacOS

### Additional context

test build

Start with the API Spec Test rule for eth_getEncryptionPublicKey and trace the rejection handling for this JSON-RPC method. Compare its response with the expected 4001 error and the observed -32603 error. Done means a rejected request returns code 4001 with the specified message.

Written by the indexing model from the issue text.