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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

asynchronous = True
        stdin = True
    try:
        cwd = os.getcwd() if inherit_cwd else None
        if not asynchronous:
            if stdin:
                return subprocess.check_output(cmd, shell=True, stderr=stderr, env=env_dict,
                    stdin=subprocess.PIPE, cwd=cwd)
            output = subprocess.check_output(cmd, shell=True, stderr=stderr, env=env_dict, cwd=cwd)
            return output.decode(config.DEFAULT_ENCODING)
        
        with mutex_popen:
            stdin_arg = subprocess.PIPE if stdin else None
            stdout_arg = open(outfile, 'ab') if isinstance(outfile, six.string_types) else outfile
            stderr_arg = stderr
            if tty:
                
                import pty
                master_fd, slave_fd = pty.openpty()
                stdin_arg = slave_fd
                stdout_arg = stderr_arg = None
            
            kwargs = {}
            if is_linux() or is_mac_os():
                kwargs['preexec_fn'] = os.setsid
            process = subprocess.Popen(cmd, shell=True, stdin=stdin_arg, bufsize=-1,
                stderr=stderr_arg, stdout=stdout_arg, env=env_dict, cwd=cwd, **kwargs)
            if tty:
                
                def pipe_streams(*args):