### Is there an existing issue for this?

- [X] I have searched the existing issues

### Current Behavior

Currently, when passing `$$.Execution.StartTime` as a parameter to a SFN lambda, it is coming in in the format `HH:MM:SS.###`.

### Expected Behavior

`$$.Execution.StartTime` should be an ISO 8601 datetime string.

### How are you starting LocalStack?

With a docker-compose file

### Steps To Reproduce

This is run in a docker compose file.

Step function definition is

```json
{
  "Comment": "Sample SFN",
  "StartAt": "SampleLambda",
  "States": {    
    "SampleLambda": {
      "Type": "Task",
      "Resource": "arn:aws:states:::lambda:invoke",
      "End": true,
      "Parameters": {
        "FunctionName": "Sample-Function",
        "Payload": {
          "data": {
            "startDateTime.$": "$$.Execution.StartTime"
          }
        }
      }
    }
  }
}
```

### Environment

```markdown
- OS: Mac OS Ventura 13.6.1
- LocalStack:
LocalStack version: 3.0.1.dev
LocalStack build date: 2023-11-20
LocalStack build git hash: 3e32b438
```


### Anything else?

Thank you so much for your hard work.
def describe(self) -> MapRunItemCounts:
        return MapRunItemCounts(
            aborted=self.aborted.get(),
            failed=self.failed.get(),
            pending=self.pending.get(),
            resultsWritten=self.results_written.get(),
            running=self.running.get(),
            succeeded=self.succeeded.get(),
            timedOut=self.timed_out.get(),
            total=self.total.get(),
        )
class MapRunRecord:
    update_event: Final[threading.Event]
    map_state_machine_arn: Final[
        LongArn
    ]  
    execution_arn: Final[Arn]
    map_run_arn: Final[LongArn]
    max_concurrency: int
    execution_counter: Final[ExecutionCounter]
    item_counter: Final[ItemCounter]
    start_date: Timestamp
    status: MapRunStatus
    stop_date: Optional[Timestamp]
    
    tolerated_failure_count: int
    tolerated_failure_percentage: float
    def __init__(self, state_machine_arn: Arn, execution_arn: Arn, max_concurrency: int):