### Is there an existing issue for this?

- [X] I have searched the existing issues

### Current Behavior

In AWS, DescribeSubnet Response returns:
```
<?xml version="1.0" encoding="UTF-8"?>\n
    <Response>
        <Errors>
            <Error>
                <Code>InvalidSubnetID.NotFound</Code>
                <Message>The subnet ID \'test\' does not exist</Message>
            </Error>
        </Errors>
    <RequestID>f6d041c1-1c96-4720-af30-77745504e2ba</RequestID>
</Response>
```

whereas localstack returns:
```
<?xml version=\'1.0\' encoding=\'utf-8\'?>\n<Errors xmlns="http://ec2.amazonaws.com/doc/2016-11-15">
    <Error>
        <Code>InvalidSubnetID.NotFound</Code>
        <Message>aaThe subnet ID \'vpc-test\' does not exist</Message>
    </Error>
    <RequestID>EADJHWMM796CI5FT10XGFMGOXIPCBAHBWINMV0HR6SKBRODGCU5J</RequestID>
</Errors>

```

### Expected Behavior

It should return correct response structure. It causes terraform to complain.

### How are you starting LocalStack?

Custom (please describe below)

### Steps To Reproduce

#### How are you starting localstack (e.g., `bin/localstack` command, arguments, or `docker-compose.yml`)

    make start

#### Client commands (e.g., AWS SDK code snippet, or sequence of "awslocal" commands)

     awslocal ec2 describe-subnets --subnet-ids vpc-test --debug


### Environment

```markdown
- OS: M1 MacOS
- LocalStack: 1.0.2.dev
```


### Anything else?

Probably `call_moto` function in `localstack/services/moto.py` is changing the error code structure.
self,
        event_type: str,
        content: Union[str, bytes] = "",
        error_code: Optional[str] = None,
        error_message: Optional[str] = None,
    ) -> bytes:
        """
        Encodes the given event payload according to AWS specific binary event encoding.
        A specification of the format can be found in the AWS docs:
        https://docs.aws.amazon.com/AmazonS3/latest/API/RESTSelectObjectAppendix.html
        :param content: string or bytes of the event payload
        :param event_type: type of the event. Usually the name of the event shape 
                            "initial-response".
        :param error_code: Optional. Error code if the payload represents an error.
        :param error_message: Optional. Error message if the payload represents an error.
        :return: bytes with the AWS-specific encoded event payload
        """
        # determine the event type (error if an error message or an error code is set)
        if error_message or error_code:
            message_type = "error"
        else: