As an enhancement to https://github.com/localstack/localstack/pull/1194

It would be really helpful to send the Lambda name, either as data, a header, or as part of the URL.

At code location: https://github.com/localstack/localstack/blob/03c6f4bf250edd18eb818ed65090f508636b0bff/localstack/services/awslambda/lambda_api.py#L696

I can likely open a PR to handle this given some feedback on the feature and potential design.

Right now all I see is the following (using `npx http-echo-server`):
```
[socket#8] event: data
--> POST / HTTP/1.1
--> Host: 192.168.1.x:3000
--> User-Agent: python-requests/2.22.0
--> Accept-Encoding: gzip, deflate
--> Accept: */*
--> Connection: keep-alive
--> Content-Length: 9
--> Content-Type: application/x-www-form-urlencoded
-->
-->
[socket#8] event: data
--> Name=test
```
return not_found_error(arn)
    for tag_key in tag_keys:
        func_details.tags.pop(tag_key, None)
    return jsonify({})
@app.route('/2019-09-25/functions/<function>/event-invoke-config', methods=['PUT'])
def put_function_event_invoke_config(function):
    """ Updates the configuration for asynchronous invocation for a function
        ---
        operationId: PutFunctionEventInvokeConfig
        parameters:
            - name: 'function'
              in: path
            - name: 'qualifier'
              in: path
            - name: 'request'
              in: body
    """
    data = json.loads(to_str(request.data))
    function_arn = func_arn(function)
    lambda_obj = arn_to_lambda[function_arn]
    response = lambda_obj.put_function_event_invoke_config(data)
    return jsonify({
        'LastModified': response.last_modified,
        'FunctionArn': str(function_arn),
        'MaximumRetryAttempts': response.max_retry_attempts,
        'MaximumEventAgeInSeconds': response.max_event_age,
        'DestinationConfig': {
            'OnSuccess': {
                'Destination': str(response.on_successful_invocation)
            },