sqs.changeMessageVisibility according to [this](https://docs.aws.amazon.com/AWSSimpleQueueService/latest/APIReference/API_ChangeMessageVisibility.html#API_ChangeMessageVisibility_Examples) makes a request directly to the Queue's URL rather than via the SQS Endpoint. (I'm already setting SQS endpoint to LOCALSTACK_HOSTNAME - makes no difference for this call)..

In localstack the queue URL host returned is by default set to the value of HOSTNAME_EXTERNAL, which I'm setting to localstack, but calling this method within a lambda, does not work and I get the error:

```
UnknownEndpoint: Inaccessible host: `localstack'. This service may not be available in the `us-east-1' region. 
```

So, how can I make the queue URL accessible from within a lambda using localstack? Effectively I need to make **http://localstack** accessible from within lambda.

I'm using the following cmd to start localstack:

```
LAMBDA_EXECUTOR=docker-reuse DEBUG=1 LAMBDA_REMOTE_DOCKER=0 DATA_DIR=/tmp/localstack/data HOSTNAME_EXTERNAL=localstack localstack start
```
class TestAPIGatewayIntegrations(unittest.TestCase):
    
    APIGATEWAY_DATA_INBOUND_TEMPLATE = """{
        "StreamName": "%s",
        "Records": [
            #set( $numRecords = $input.path('$.records').size() )
            #if($numRecords > 0)
            #set( $maxIndex = $numRecords - 1 )
            #foreach( $idx in [0..$maxIndex] )
            #set( $elem = $input.path("$.records[${idx}]") )
            #set( $elemJsonB64 = $util.base64Encode($elem.data) )
            {
                "Data": "$elemJsonB64",
                "PartitionKey": #if( $elem.partitionKey != '')"$elem.partitionKey"
                                #else"$elemJsonB64.length()"#end
            }#if($foreach.hasNext),#end
            #end
            #end
        ]
    }"""
    
    API_PATH_DATA_INBOUND = '/data'
    API_PATH_HTTP_BACKEND = '/hello_world'
    API_PATH_LAMBDA_PROXY_BACKEND = '/lambda/foo1'
    API_PATH_LAMBDA_PROXY_BACKEND_WITH_PATH_PARAM = '/lambda/{test_param1}'
    API_PATH_LAMBDA_PROXY_BACKEND_ANY_METHOD = '/lambda-any-method/foo1'
    API_PATH_LAMBDA_PROXY_BACKEND_ANY_METHOD_WITH_PATH_PARAM = '/lambda-any-method/{test_param1}'
    
    TEST_STREAM_KINESIS_API_GW = 'test-stream-api-gw'
    TEST_SQS_QUEUE = 'test-sqs-queue-api-gw'