### Is there an existing issue for this?

- [X] I have searched the existing issues

### Current Behavior

Currently the VTL template for `request_templates` is not processed properly:

```
#set( $body = $input.json("$") )

#macro( loop $map )
{
    #foreach($key in $map.keySet())
        #set( $k = $util.escapeJavaScript($key) )
        #set( $v = $util.escapeJavaScript($map.get($key)).replaceAll("\\'", "'") )
        "$k": "$v"
        #if( $foreach.hasNext ) , #end
    #end
}
#end

{
    "enhancedAuthContext": #loop($context.authorizer),

    "headers": #loop($input.params().header),

    "query": #loop($input.params().querystring),

    "path": #loop($input.params().path),

    "identity": #loop($context.identity),

    "stageVariables": #loop($stageVariables),
}
EOF
}
```

results in,

```
'

{
    "enhancedAuthContext": {
    }
,

    "headers": {
    }
,

    "query": {
    }
,

    "path": {
    }
,

    "identity": {
    }
,

    "stageVariables": {
    }
,
}
'
```

### Expected Behavior

The template should be rendered and have the JSON properties.

### 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`)

    docker run localstack/localstack

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

    awslocal s3 mb s3://mybucket


### Environment

```markdown
- OS: MacOS
- LocalStack: 0.14
```


### Anything else?

This example can be used to validate.
https://github.com/localstack/localstack-terraform-samples/tree/master/apigateway-lambda-velocity
api_id,
        parent_id,
        path_suffix=path_suffix,
        resources=resources,
        region_name=region_name,
    )
def create_api_gateway(
    name,
    description=None,
    resources=None,
    stage_name=None,
    enabled_api_keys=None,
    env=None,
    usage_plan_name=None,
    region_name=None,
    auth_creator_func=None,  
):
    if enabled_api_keys is None:
        enabled_api_keys = []
    client = connect_to_service("apigateway", env=env, region_name=region_name)
    resources = resources or []
    stage_name = stage_name or "testing"
    usage_plan_name = usage_plan_name or "Basic Usage"
    description = description or 'Test description for API "%s"' % name
    LOG.info('Creating API resources under API Gateway "%s".', name)
    api = client.create_rest_api(name=name, description=description)
    api_id = api["id"]
    auth_id = None
    if auth_creator_func:
        auth_id = auth_creator_func(api_id)