### Is there an existing issue for this?

- [X] I have searched the existing issues

### Current Behavior

`#return` macro for AppSync is not supported

```
- ["Error in template '<string>' at position 48-60 in expression: #return($v1)\nException: no such macro: return\n\nGraphQL request:3:11\n2 |         {\n3 |           hi2 {\n  |           ^\n4 |             value"] None
```

### Expected Behavior

`#return` is a valid command in AppSync Resolver Velocity request and response templates.

https://docs.aws.amazon.com/appsync/latest/devguide/aws-appsync-directives.html 

### How are you starting LocalStack?

With the `localstack` script

### Steps To Reproduce

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

    localstack start

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

1. `CDKDeployment`
2. GraphQL Rest API to `localstack`

3. AppSync resolver with response template:

```vtl
#set($v1 = {})
$util.qr($v1.put('value', 'hi'))
#return($v1)"
```

```sdl
schema {
  query: Query
}
type valueObj {
  value: String
}
type Query {
  hi2: valueObj
}
```

4. Query AppSync

```sdl
Query {
   hi2
}
```



### Environment

```markdown
- OS: Ubuntu/WSL2
- LocalStack: 0.14.2.1
```


### Anything else?

The same code runs fine on AWS/AppSync.
ctx = ApiInvocationContext("POST", "/", b"", {})
        ctx.resource = {"resourceMethods": {"GET": {}}}
        validator = RequestValidator(ctx, None)
        self.assertTrue(validator.is_request_valid())
    def test_if_request_is_valid_with_no_validator(self):
        ctx = ApiInvocationContext("POST", "/", b"", {})
        ctx.api_id = "deadbeef"
        ctx.resource = {"resourceMethods": {"POST": {"requestValidatorId": " "}}}
        validator = RequestValidator(ctx, None)
        self.assertTrue(validator.is_request_valid())
    def test_if_request_has_body_validator(self):
        apigateway_client = self._mock_client()
        apigateway_client.get_request_validator.return_value = {"validateRequestBody": True}
        apigateway_client.get_model.return_value = {"schema": '{"type": "object"}'}
        ctx = ApiInvocationContext("POST", "/", '{"id":"1"}', {})
        ctx.api_id = "deadbeef"
        ctx.resource = {
            "resourceMethods": {
                "POST": {
                    "requestValidatorId": "112233",
                    "requestModels": {"application/json": "schemaName"},
                }
            }
        }
        validator = RequestValidator(ctx, apigateway_client)
        self.assertTrue(validator.is_request_valid())
    def test_request_validate_body_with_no_request_model(self):