### 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_
)
        sqs_client.set_queue_attributes(
            QueueUrl=queue_url_ok, Attributes={"Policy": get_sqs_policy(arn_queue_ok, topic_arn_ok)}
        )
        alarm_name = "test-alarm"
        alarm_description = "Test Alarm when CPU exceeds 50 percent"
        expected_trigger = {
            "MetricName": "CPUUtilization-3",
            "Namespace": "AWS/EC2",
            "Unit": "Percent",
            "Period": 300,
            "EvaluationPeriods": 2,
            "ComparisonOperator": "GreaterThanThreshold",
            "Threshold": 50.0,
            "TreatMissingData": "ignore",
            "EvaluateLowSampleCountPercentile": "",
            "Dimensions": [{"value": "i-0317828c84edbe100", "name": "InstanceId"}],
            "StatisticType": "Statistic",
            "Statistic": "AVERAGE",
        }
        try:
            
            subscription_alarm = sns_client.subscribe(
                TopicArn=topic_arn_alarm, Protocol="sqs", Endpoint=arn_queue_alarm
            )
            subscription_ok = sns_client.subscribe(
                TopicArn=topic_arn_ok, Protocol="sqs", Endpoint=arn_queue_ok
            )
            
            cloudwatch_client.put_metric_alarm(