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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

t1 = now_utc()
        t2 = now_utc(millis=True)
        self.assertLessEqual(t2 - t1, 1)
def run_parallel_download():
    file_length = 10000000
    class DownloadListener(ProxyListener):
        def forward_request(self, method, path, data, headers):
            sleep_time = int(path.replace('/', ''))
            time.sleep(sleep_time)
            response = Response()
            response.status_code = 200
            response._content = ('%s' % sleep_time) * file_length
            return response
    test_port = 12124
    tmp_file_pattern = '/tmp/test.%s'
    proxy = GenericProxy(port=test_port, update_listener=DownloadListener())
    proxy.start()
    def do_download(param):
        tmp_file = tmp_file_pattern % param
        TMP_FILES.append(tmp_file)
        download('http://localhost:%s/%s' % (test_port, param), tmp_file)
    values = (1, 2, 3)
    parallelize(do_download, values)
    proxy.stop()
    for val in values:
        tmp_file = tmp_file_pattern % val
        assert len(load_file(tmp_file)) == file_length