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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

import time
import yaml
import datetime
import unittest
from requests.models import Response
from localstack.utils.aws import aws_stack
from localstack.services.generic_proxy import GenericProxy, ProxyListener
from localstack.utils.common import (
    download, parallelize, TMP_FILES, load_file, parse_chunked_data, json_safe, now_utc)
class TestMisc(unittest.TestCase):
    def test_environment(self):
        env = aws_stack.Environment.from_json({'prefix': 'foobar1'})
        self.assertEqual(env.prefix, 'foobar1')
        env = aws_stack.Environment.from_string('foobar2')
        self.assertEqual(env.prefix, 'foobar2')
    def test_parse_chunked_data(self):
        
        chunked = '4\r\nWiki\r\n5\r\npedia\r\nE\r\n in\r\n\r\nchunks.\r\n0\r\n\r\n'
        expected = 'Wikipedia in\r\n\r\nchunks.'
        parsed = parse_chunked_data(chunked)
        self.assertEqual(parsed.strip(), expected.strip())
    def test_convert_yaml_date_strings(self):
        yaml_source = 'Version: 2012-10-17'
        obj = yaml.safe_load(yaml_source)
        self.assertIn(type(obj['Version']), (datetime.date, str))
        if isinstance(obj['Version'], datetime.date):
            obj = json_safe(obj)
            self.assertEqual(type(obj['Version']), str)
            self.assertEqual(obj['Version'], '2012-10-17')
    def test_timstamp_millis(self):