### Is there an existing issue for this?

- [X] I have searched the existing issues

### Current Behavior

When attempting to sign some document using Localstack KMS inside a lambda container (also running on localstack), the localstack KMS listener returns some unknown error.

The KMS key and lambda containers have been created from the same CDK app deploy, and I can see all the resources in the localstack web console.

The test application I'm using to prove this behaviour is available here:
https://github.com/LukaHedt/localstack_kms_test

Instructions to run are in the main Readme, and the `/localstack/Readme.md` file.

`aws-sdk` returns an unknown error, and the localstack docker logs that I receive are available here:
https://pastebin.com/58Z3fXi3

Have done an amount of testing and can confidently claim the following:
- Have tested on multiple machines with the same outcome
- Doesn’t make a difference if I specify an ARN or a KeyID in the signing request
- Downgrading localstack versions either didn’t make a difference, or I couldn’t actually deploy a localstack container with version 0.12.20 or lower.

### Expected Behavior

KMS Sign should return a signature for the given payload.

### How are you starting LocalStack?

With a docker-compose file

### Steps To Reproduce

Test application demonstrating the current behaviour is available here:

https://github.com/LukaHedt/localstack_kms_test

Full instructions to run are in the `/localstack/Readme.md` file.


### Environment

```markdown
- OS: MacOS Monteray 12.3
- LocalStack: 0.14.0
```


### Anything else?

_No response_
import logging
import os
import platform
from localstack import config
from localstack.constants import TEST_AWS_ACCOUNT_ID
from localstack.services.infra import (
    do_run,
    log_startup_message,
    start_moto_server,
    start_proxy_for_service,
)
from localstack.services.install import INSTALL_PATH_KMS_BINARY_PATTERN
from localstack.utils.common import get_arch, get_free_tcp_port, wait_for_port_open
LOG = logging.getLogger(__name__)
KMS_PROVIDER = (os.environ.get("KMS_PROVIDER") or "").strip() or "moto"
def start_kms_local(port=None, backend_port=None, asynchronous=None, update_listener=None):