### 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.
"headers": $loop,
    #set( $map = $input.params().querystring )
    "query": $loop,
    #set( $map = $input.params().path )
    "path": $loop,
    #set( $map = $context.identity )
    "identity": $loop,
    #set( $map = $stageVariables )
    "stageVariables": $loop,
}
"""
class TestMessageTransformationBasic:
    def test_return_macro(self):
        template = """
        #set($v1 = {})
        $v1.put('foo', 'bar')
        #return($v1)
        """
        result = render_velocity_template(template, {})
        expected = {"foo": "bar"}
        assert json.loads(result) == expected
class TestMessageTransformationApiGateway:
    def test_construct_json_using_define(self):
        template = APIGW_TEMPLATE_CONSTRUCT_JSON
        data = {"p1": {"test": 123}, "p2": {"foo": "bar", "foo2": False}}
        variables = {"input": {"body": data}}
        result = ApiGatewayVtlTemplate().render_vtl(template, variables).strip()
        result = json.loads(result)
        assert result == {"p0": True, **data}
    def test_array_size(self):