### Is there an existing issue for this?

- [X] I have searched the existing issues

### Current Behavior

When calling 

`cloudWatchClient.EnableAlarmActions(&cloudwatch.EnableAlarmActionsInput{AlarmNames: alarmNames})`

with golang I receive a SerializationError with bytes in the error message saying: 

`<!DOCTYPE HTM |UBLIC "-//W3C//DTD HTML 3.2 Final//EN">.<title>500 Internal Server Error</title>.<h1>Internal Server Error</h1>.<p>The server encountered an internal error and was unable to complete your request. Either the server is overloaded or there is an error in the application.`

I believe this is a bug, since other cloudwatch operations like "DescribeAlarms" work flawlessly with the same client.

### Expected Behavior

I expected the call to go through without any errors

### How are you starting LocalStack?

With a `docker run` command

### Steps To Reproduce

Start localstack, create alarms and call cloudwatch "EnableAlarmActions"

### Environment

_No response_

### Anything else?

_No response_
import json
import logging
from xml.sax.saxutils import escape
from moto.cloudwatch import cloudwatch_backends
from moto.cloudwatch.models import CloudWatchBackend, FakeAlarm
from localstack.aws.api import CommonServiceException, RequestContext, handler
from localstack.aws.api.cloudwatch import (
    AlarmNames,
    AmazonResourceName,
    CloudwatchApi,
    ListTagsForResourceOutput,
    PutCompositeAlarmInput,
    PutMetricAlarmInput,
    TagKeyList,
    TagList,
    TagResourceOutput,
    UntagResourceOutput,
)
from localstack.http import Request
from localstack.services import moto
from localstack.services.cloudwatch.alarm_scheduler import AlarmScheduler
from localstack.services.edge import ROUTER
from localstack.services.plugins import SERVICE_PLUGINS, ServiceLifecycleHook
from localstack.utils.aws import aws_stack
from localstack.utils.patch import patch
from localstack.utils.sync import poll_condition
from localstack.utils.tagging import TaggingService
from localstack.utils.threads import start_worker_thread
PATH_GET_RAW_METRICS = "/cloudwatch/metrics/raw"
LOG = logging.getLogger(__name__)