### 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_
"AlarmActions": alarm.alarm_actions or "",
        "InsufficientDataActions": alarm.insufficient_data_actions or "",
    }
    
    details = {
        "MetricName": alarm.metric_name or "",
        "Namespace": alarm.namespace or "",
        "Unit": alarm.unit or "",
        "Period": int(alarm.period) if alarm.period else 0,
        "EvaluationPeriods": int(alarm.evaluation_periods) if alarm.evaluation_periods else 0,
        "ComparisonOperator": alarm.comparison_operator or "",
        "Threshold": float(alarm.threshold) if alarm.threshold else 0.0,
        "TreatMissingData": alarm.treat_missing_data or "",
        "EvaluateLowSampleCountPercentile": alarm.evaluate_low_sample_count_percentile or "",
    }
    
    dimensions = []
    if alarm.dimensions:
        for d in alarm.dimensions:
            dimensions.append({"value": d.value, "name": d.name})
    details["Dimensions"] = dimensions or ""
    if alarm.statistic:
        details["StatisticType"] = "Statistic"
        details["Statistic"] = alarm.statistic.upper()  
    elif alarm.extended_statistic:
        details["StatisticType"] = "ExtendedStatistic"
        details["ExtendedStatistic"] = alarm.extended_statistic
    response["Trigger"] = details
    return json.dumps(response)
class ValidationError(CommonServiceException):