### Is there an existing issue for this?

- [X] I have searched the existing issues and read the documentation

### Question

Using a websocket apigatewayv2 in localstack and i need to change the body of the request e.g. add the connectionid, which is something i can do with a HTTP integration on the AWS gateway, however when I try this with localstack i receive the following error "Unsupported integration type "HTTP" for Websocket API ID" and then prints the ID of the API, if this feature is not enabled then how should we test the actual API where the connectionId and other things are added to the request body

### Anything else?

_No response_
if isinstance(s, six.binary_type) and exclude_binary:
        return False
    if isinstance(s, str):
        return True
    if include_unicode and isinstance(s, six.text_type):
        return True
    return False
def is_string_or_bytes(s):
    return is_string(s) or isinstance(s, six.string_types) or isinstance(s, bytes)
def is_base64(s):
    regex = r"^(?:[A-Za-z0-9+/]{4})*(?:[A-Za-z0-9+/]{2}==|[A-Za-z0-9+/]{3}=)?$"
    return is_string(s) and re.match(regex, s)
def md5(string: Union[str, bytes]) -> str:
    m = hashlib.md5()
    m.update(to_bytes(string))
    return m.hexdigest()
def select_attributes(obj: Dict, attributes: List[str]) -> Dict:
    """Select a subset of attributes from the given dict (returns a copy)"""
    attributes = attributes if is_list_or_tuple(attributes) else [attributes]
    return {k: v for k, v in obj.items() if k in attributes}
def remove_attributes(obj: Dict, attributes: List[str], recursive: bool = False) -> Dict:
    """Remove a set of attributes from the given dict (in-place)"""
    if recursive:
        def _remove(o, **kwargs):