### Is there an existing issue for this?

- [X] I have searched the existing issues

### Current Behavior

When starting the transcription job in response job object is null:

<img width="1154" alt="Screenshot 2023-04-03 at 09 21 09" src="https://user-images.githubusercontent.com/454412/229447066-1671f811-da49-478d-bf24-252f30b17699.png">


### Expected Behavior

Response from the real AWS stack - job object is not null

<img width="1161" alt="Screenshot 2023-04-03 at 09 30 13" src="https://user-images.githubusercontent.com/454412/229441498-06125248-3b68-4679-8204-0163e8245db6.png">


### How are you starting LocalStack?

Custom (please describe below)

### Steps To Reproduce

Using test containers, reproducing project can be found here:

https://github.com/kkocel/local-stack-transcribe-repro

### Environment

```markdown
- OS: macOS
- LocalStack: latest
```


### Anything else?

_No response_
role_name = f"role-{short_uid()}"
        result = create_role(RoleName=role_name, AssumeRolePolicyDocument=assume_policy_doc)
        role_arn = result["Role"]["Arn"]
        policy_name = f"p-{short_uid()}"
        if attach:
            
            policy_arn = create_policy_generated_document(
                effect, actions, policy_name=policy_name, resource=resource
            )
            iam_client.attach_role_policy(RoleName=role_name, PolicyArn=policy_arn)
        else:
            
            policy_document = create_policy_doc(effect, actions, resource=resource)
            policy_document = json.dumps(policy_document)
            iam_client.put_role_policy(
                RoleName=role_name, PolicyName=policy_name, PolicyDocument=policy_document
            )
        return role_name, role_arn
    return _create_role_with_policy
@pytest.fixture
def create_user_with_policy(iam_client, create_policy_generated_document, create_user):
    def _create_user_with_policy(effect, actions, resource=None):
        policy_arn = create_policy_generated_document(effect, actions, resource=resource)
        username = f"user-{short_uid()}"
        create_user(UserName=username)
        iam_client.attach_user_policy(UserName=username, PolicyArn=policy_arn)
        keys = iam_client.create_access_key(UserName=username)["AccessKey"]
        return username, keys
    return _create_user_with_policy