### Is there an existing issue for this?

- [X] I have searched the existing issues

### Feature description

Currently, the default port range for external services is configured in `config.py` as follows:
https://github.com/localstack/localstack/blob/075a6fcfcc29af99e1997d73abea6e88351f3c84/localstack/config.py#L462-L472
This means that the default service range is: (4510,4540]
But the example `docker-compose.yml` states (4510, 4530):
https://github.com/localstack/localstack/blob/075a6fcfcc29af99e1997d73abea6e88351f3c84/docker-compose.yml#L12

The currently stated 20 ports can already be somewhat limiting if a lot of external services are started (f.e. lots of clusters or databases). Therefore the range should be broadened and correctly defined in our example `docker-compose.yml` file.

### 🧑‍💻 Implementation

- [x] Broaden the service port range to 50 ports.
- [x] Update the example docker-compose file.

### Anything else?

_No response_
"""
    Returns True if running in a docker container, else False
    Ref. https://docs.docker.com/config/containers/runmetrics/#control-groups
    """
    if OVERRIDE_IN_DOCKER:
        return True
    
    if os.path.exists("/.dockerenv"):
        return True
    if os.path.exists("/run/.containerenv"):
        return True
    if not os.path.exists("/proc/1/cgroup"):
        return False
    try:
        if any(
            [
                os.path.exists("/sys/fs/cgroup/memory/docker/"),
                any(
                    "docker-" in file_names
                    for file_names in os.listdir("/sys/fs/cgroup/memory/system.slice")
                ),
                os.path.exists("/sys/fs/cgroup/docker/"),
                any(
                    "docker-" in file_names
                    for file_names in os.listdir("/sys/fs/cgroup/system.slice/")
                ),
            ]
        ):
            return False