### 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_
patches = Patches(
        [
            Patch.function(
                alarm_scheduler.get_metric_alarm_details_for_alarm_arn,
                mock_metric_alarm_details,
                pass_target=False,
            ),
            Patch.function(
                alarm_scheduler.get_cloudwatch_client_for_region_of_alarm,
                mock_cloudwatch_client,
                pass_target=False,
            ),
            Patch.function(
                alarm_scheduler.collect_metric_data,
                mock_collect_metric_data,
                pass_target=False,
            ),
        ]
    )
    with patches:
        alarm_scheduler.calculate_alarm_state("helloworld")
        assert len(mock_client.mock_calls) == expected_calls
        if expected_calls != 0:
            expected_calls = [
                call.set_alarm_state(
                    AlarmName="test-alarm", StateValue=expected_state, StateReason=ANY
                )
            ]
            mock_client.assert_has_calls(expected_calls)