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# Type of request: This is a ...

[X] bug report
[ ] feature request

# Detailed description

Running localstack in a Docker (v19.03.8) container on macOS 10.15.6, some log output lines appears in triplicate. It appears that the messages, such as access log entries, are generated by Flask. The lines only appear if **DEBUG** is set in the environment; if **DEBUG** is not set, no access log messages appear, but if **DEBUG** is set, they appear three times each.

This is certainly not keeping me from getting things done -- it's just a little confusing when troubleshooting calls into localstack. Thank you in advance for this amazing project and any help you can offer!

## Expected behavior

One line of log output per event, such as an access log line.

## Actual behavior

Three identical copies of each log line are generated.

# Steps to reproduce

## Command used to start LocalStack

    docker run -it -p 4566:4566 -e DEBUG=1 -e SERVICES=s3 localstack/localstack


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

    awslocal s3 mb s3://stuff

## Console output
    ...
    Running on 0.0.0.0:4566 over https (CTRL + C to quit)
    2020-07-27T21:09:38:INFO:localstack.multiserver: Starting multi API server process on port 40641
    Running on 0.0.0.0:4572 over http (CTRL + C to quit)
    Running on 0.0.0.0:40641 over http (CTRL + C to quit)
    2020-07-27 21:09:39,891:API:  * Running on http://0.0.0.0:46165/ (Press CTRL+C to quit)
    2020-07-27 21:09:39,891:API:  * Running on http://0.0.0.0:46165/ (Press CTRL+C to quit)
    2020-07-27 21:09:39,891:API:  * Running on http://0.0.0.0:46165/ (Press CTRL+C to quit)
    ...  
    2020-07-27 21:09:48,942:API: 127.0.0.1 - - [27/Jul/2020 21:09:48] "PUT /stuff HTTP/1.1" 200 -
    2020-07-27 21:09:48,942:API: 127.0.0.1 - - [27/Jul/2020 21:09:48] "PUT /stuff HTTP/1.1" 200 -
    2020-07-27 21:09:48,942:API: 127.0.0.1 - - [27/Jul/2020 21:09:48] "PUT /stuff HTTP/1.1" 200 -
plugin_configs = load_plugins()
    
    canonicalize_api_names()
    entrypoint = os.environ.get('ENTRYPOINT', '')
    cmd = os.environ.get('CMD', '')
    user_flags = config.DOCKER_FLAGS
    image_name = get_docker_image_to_start()
    service_ports = config.SERVICE_PORTS
    force_noninteractive = os.environ.get('FORCE_NONINTERACTIVE', '')
    
    plugin_run_params = ' '.join([
        entry.get('docker', {}).get('run_flags', '') for entry in plugin_configs])
    
    port_mappings = PortMappings()
    
    user_flags = extract_port_flags(user_flags, port_mappings)
    plugin_run_params = extract_port_flags(plugin_run_params, port_mappings)
    
    if service_ports.get('edge') == 0:
        service_ports.pop('edge')
    service_ports.pop('dashboard', None)
    for port in service_ports.values():
        port_mappings.add(port)
    env_str = ''
    for env_var in config.CONFIG_ENV_VARS:
        value = os.environ.get(env_var, None)
        if value is not None:
            env_str += '-e %s="%s" ' % (env_var, value)
    data_dir_mount = ''
    data_dir = os.environ.get('DATA_DIR', None)