### 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_
{"TagKey": tag["Key"], "TagValue": tag["Value"]}
                    for tag in props.get("Tags", [])
                ]
            if props.get("Description"):
                params["Description"] = props["Description"]
            if props.get("KeySpec"):
                params["KeySpec"] = props["KeySpec"]
            new_key = kms_client.create_key(**params)
            key_id = new_key["KeyMetadata"]["KeyId"]
            resource.resource_json["PhysicalResourceId"] = key_id
            
            if props.get("EnableKeyRotation", False):
                kms_client.enable_key_rotation(KeyId=key_id)
            else:
                kms_client.disable_key_rotation(KeyId=key_id)
            if props.get("Enabled", True):
                kms_client.enable_key(KeyId=key_id)
            else:
                kms_client.disable_key(KeyId=key_id)
        return {
            "create": [
                {"function": _create},
            ],
            "delete": {
                
                "function": "schedule_key_deletion",
                "parameters": {"KeyId": "PhysicalResourceId"},
            },
        }
class KMSAlias(GenericBaseModel):