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# Type of request: This is a ...

[x] bug report
[ ] feature request

# Detailed description

Localstack docker run command contains `-p 8080:8080` twice, which results in an error. When running the following command manually, I can successfully run Localstack:

```
docker run -it -e LOCALSTACK_HOSTNAME="localhost" -e TEST_AWS_ACCOUNT_ID="000000000000" -e DEFAULT_REGION="us-east-1" \
-p 443:443 \
-p 4566:4566 \
-p 8081:8081 \
-p 4567-4617:4567-4617 \
-p 8080:8080  \
--rm --privileged --name localstack_main \
-v "/private/var/folders/01/wnz8g_c95fx81w85tpl2dx300000gn/T/localstack:/tmp/localstack" -v "/var/run/docker.sock:/var/run/docker.sock" -e DOCKER_HOST="unix:///var/run/docker.sock" -e HOST_TMP_FOLDER="/private/var/folders/01/wnz8g_c95fx81w85tpl2dx300000gn/T/localstack" "localstack/localstack"
```

**OS:** MacOS Mojave 10.14.6
**Docker version:** Docker version 19.03.8, build afacb8b

## Expected behavior

Running `localstack start` should set up the stack as expected.

## Actual behavior

Running `localstack start` results in the following Docker error:
```
docker: Error response from daemon: Ports are not available: /forwards/expose/port returned unexpected status: 500.
ERRO[0000] error waiting for container: context canceled
```

# Steps to reproduce
1. Install Localstack - `pip install localstack`
2. Run Localstack - `localstack start`
3. Error is displayed

## Command used to start LocalStack
`localstack start`

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

if hasattr(pip_mod, 'main'):
        return pip_mod.main(args)
    import pip._internal
    if hasattr(pip._internal, 'main'):
        return pip._internal.main(args)
    import pip._internal.main
    return pip._internal.main.main(args)
def load_plugin_from_path(file_path, scope=None):
    if os.path.exists(file_path):
        module = re.sub(r'(^|.+/)([^/]+)/plugins.py', r'\2', file_path)
        method_name = 'register_localstack_plugins'
        scope = scope or PLUGIN_SCOPE_SERVICES
        if scope == PLUGIN_SCOPE_COMMANDS:
            method_name = 'register_localstack_commands'
        try:
            namespace = {}
            exec('from %s.plugins import %s' % (module, method_name), namespace)
            method_to_execute = namespace[method_name]
        except Exception as e:
            if (not re.match(r'.*cannot import name .*%s.*' % method_name, str(e)) and
                    ('No module named' not in str(e))):
                LOG.debug('Unable to load plugins from module %s: %s' % (module, e))
            return
        try:
            return method_to_execute()
        except Exception as e:
            if not os.environ.get(ENV_SCRIPT_STARTING_DOCKER):
                LOG.warning('Unable to load plugins from file %s: %s' % (file_path, e))
def load_plugins(scope=None):