### Is there an existing issue for this?

- [X] I have searched the existing issues

### Current Behavior

When I create an ingress rule for a Redshift cluster security group, the rule doesn't stick: I'll describe cluster security groups, and the rule won't be applied.

### Expected Behavior

From [this issue](https://github.com/localstack/localstack/issues/2775), I figured that the rule would be properly applied.

### How are you starting LocalStack?

With a docker-compose file

### Steps To Reproduce

#### How are you starting localstack (e.g., `bin/localstack` command, arguments, or `docker-compose.yml`)

```sh
services:
  localstack:
    image: localstack/localstack:latest
    ports:
      - 4563-4584:4563-4584
    volumes:
      - ./volume:/var/lib/localstack
```

#### Client commands (e.g., AWS SDK code snippet, or sequence of "awslocal" commands)

```sh
awslocal redshift create-cluster-security-group --cluster-security-group-name "group-name" --description "Security group description"
awslocal redshift authorize-cluster-security-group-ingress --cluster-security-group-name "group-name" --cidrip 192.168.100.101/32
awslocal redshift describe-cluster-security-groups
```


### Environment

```markdown
- OS: Ubuntu 20.04
- LocalStack: latest
```


### Anything else?

This was tested with and without Pro. I'm curious if this should be a Pro-only feature though.
from moto.redshift import responses as redshift_responses
from localstack.aws.api.redshift import RedshiftApi
from localstack.utils.common import recurse_object
from localstack.utils.patch import patch
@patch(redshift_responses.itemize)
def itemize(fn, data, parent_key=None, *args, **kwargs):
    
    list_parent_tags = ["ClusterSubnetGroups"]
    def fix_keys(o, **kwargs):
        if isinstance(o, dict):
            for k, v in o.items():
                if k in list_parent_tags:
                    if isinstance(v, dict) and "item" in v:
                        v[k[:-1]] = v.pop("item")
        return o
    result = fn(data, *args, **kwargs)
    recurse_object(result, fix_keys)
    return result
class RedshiftProvider(RedshiftApi):
    pass