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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

scope = scope or PLUGIN_SCOPE_SERVICES
    if PLUGINS_LOADED.get(scope):
        return PLUGINS_LOADED[scope]
    t1 = now_utc()
    setup_logging()
    loaded_files = []
    result = []
    
    
    search_modules = PLUGIN_MODULES
    for module in search_modules:
        file_path = None
        if isinstance(module, six.string_types):
            loader = pkgutil.get_loader(module)
            if loader:
                path = getattr(loader, 'path', '') or getattr(loader, 'filename', '')
                if '__init__.py' in path:
                    path = os.path.dirname(path)
                file_path = os.path.join(path, 'plugins.py')
        elif six.PY3 and not isinstance(module, tuple):
            file_path = os.path.join(module.module_finder.path, module.name, 'plugins.py')
        elif six.PY3 or isinstance(module[0], pkgutil.ImpImporter):
            if hasattr(module[0], 'path'):
                file_path = os.path.join(module[0].path, module[1], 'plugins.py')