### Is there an existing issue for this?

- [X] I have searched the existing issues

### Current Behavior

When attempting to list roles where permission boundaries are attached the response cannot be serialized 

`aws --endpoint-url=http://localhost:4566 iam list-roles --region ap-southeast-2`
```
An error occurred (InternalError) when calling the ListRoles operation (reached max retries: 2): exception while calling iam.ListRoles: Invalid type when serializing AttachedPermissionsBoundary: '<Element 'member' at 0xffff8275ef20>' cannot be parsed to structure.
```

### Expected Behavior

Expect that all roles are listed

### 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`)

    docker run localstack/localstack

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

* Create an IAM policy
* Create an IAM role which used the policy as a permission boundary
* Attempt to list all roles with `aws --endpoint-url=http://localhost:4566 iam list-roles --region ap-southeast-2`


### Environment

```markdown
- OS: MacOS
- LocalStack: latest
```


### Anything else?

_No response_
import logging
import re
from datetime import datetime
from typing import Optional, Pattern
from localstack.aws.api.secretsmanager import CreateSecretResponse
from localstack.aws.api.stepfunctions import CreateStateMachineOutput, StartExecutionOutput
from localstack.testing.snapshots.transformer import (
    JsonpathTransformer,
    KeyValueBasedTransformer,
    RegexTransformer,
    ResponseMetaDataTransformer,
    SortingTransformer,
)
from localstack.utils.net import IP_REGEX
LOG = logging.getLogger(__name__)
PATTERN_UUID = re.compile(
    r"[a-fA-F0-9]{8}-[a-fA-F0-9]{4}-[a-fA-F0-9]{4}-[a-fA-F0-9]{4}-[a-fA-F0-9]{12}"
)
PATTERN_ISO8601 = re.compile(
    r"(?:[1-9]\d{3}-(?:(?:0[1-9]|1[0-2])-(?:0[1-9]|1\d|2[0-8])|(?:0[13-9]|1[0-2])-(?:29|30)|(?:0[13578]|1[02])-31)|(?:[1-9]\d(?:0[48]|[2468][048]|[13579][26])|(?:[2468][048]|[13579][26])00)-02-29)T(?:[01]\d|2[0-3]):[0-5]\d:[0-5]\d(?:\.\d{1,9})?(?:Z|[+-][01]\d:?([0-5]\d)?)"
)
PATTERN_ARN = re.compile(r"arn:(aws[a-zA-Z-]*)?:([a-zA-Z0-9-_.]+)?:([^:]+)?:(\d{12})?:(.*)")
PATTERN_ARN_CHANGESET = re.compile(
    r"arn:(aws[a-zA-Z-]*)?:([a-zA-Z0-9-_.]+)?:([^:]+)?:(\d{12})?:changeSet/([^/]+)"
)