### Is there an existing issue for this?

- [X] I have searched the existing issues

### Current Behavior

Sending a message with body:
`"&quot;&quot;"`
is received on the consumer side with body:
`""""`

### Expected Behavior

Sending a message with body:
"&quot;&quot;"
is received on the consumer side with body:
"&quot;&quot;"

### 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`)

Running localstack in docker desktop on Mac using helm chart

https://localstack.github.io/helm-charts
version 0.3.7
Image version: 0.14.3

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



### Environment

```markdown
- OS: macOS Monterey
- LocalStack: 0.14.3
```


### Anything else?

_No response_
pe.type_name}."
            ) from e
    def _serialize_type_structure(
        self, body: dict, value: dict, shape: StructureShape, key: Optional[str], mime_type: str
    ):
        if value is None:
            return
        if shape.is_document_type:
            body[key] = value
        else:
            if key is not None:
                # If a key is provided, this is a result of a recursive
                # call, so we need to add a new child dict as the value
                # of the passed in serialized dict.  We'll then add
                # all the structure members as key/vals in the new serialized
                # dictionary we just created.
                new_serialized = {}
                body[key] = new_serialized
                body = new_serialized
            members = shape.members
            for member_key, member_value in value.items():
                if member_value is None:
                    continue
                try:
                    member_shape = members[member_key]
                except KeyError:
                    LOG.warning(
                        "Response object %s contains a member which is not specified: %s",
                        shape.name,
                        member_key,
                    )
                    continue
                if "name" in member_shape.serialization:
                    
                smber_key, mime_type)
    def _serialize_type_map(
        self, body: dict, value: dict, shapepe: str
    ):
        if value is None:
            return
        map_obj = {}
        body[key] = map_obj
        for sub_key, sub_value in value.items():
            if sub_value is not None:
                self._serialize(map_obj, sub_value, shape.value, sub_key, mime_type)
    def _serialize_type_list(
        self, body: dict, value: list, shape: ListShape, key: str, mime_type: str
    ):
        if value is None:
            return
        list_obj = []
        body[key] = list_obj
        f