aws_stepfunctions: addPrefix fails when added to map iterator

### Describe the bug

When using `StpeFunctionFragment` construct with map, `prefix_states()` method does not workg properly with `Map` construct used in fragment.

This feels like `add_prefix` would add prefix only to CDK constructs but not to the step function tasks inside MAP iterator elements. Issue does not exist outside of the map.

_Note_: worth to check if `Parallel` is not affected as well.

### Expected Behavior

Create `Map` element iterator items with proper prefix.

### Current Behavior

Prefix feels not to be added at proper time instant, erroring with duplicated states. The error for code example below is:
```jsii.errors.JSIIError: State with name 'The Pass' occurs in both Map The Map Iterator (Fragment 1: The Pass) and Map The Map Iterator (Fragment 2: The Pass). All states must have unique names.```

### Reproduction Steps

Minimum viable code to reproduce error:

```import aws_cdk as cdk
from aws_cdk import (
aws_stepfunctions as sfn,
Stack,
)
from constructs import Construct

class HasMapIssueFragment(sfn.StateMachineFragment):
def __init__(self, parent, fragment_id: str) -> None:
super().__init__(parent, fragment_id)

map = sfn.Map(
self,
"The Map",
).iterator(
sfn.Pass(self, "The Pass")
)

self._start_state = map.start_state
self._end_states = map.end_states
self.prefix_states(f'{fragment_id}: ')

@property
def start_state(self) -> sfn.State:
return self._start_state

@property
def end_states(self) -> list[sfn.INextable]:
return self._end_states

class HasMapIssue(Stack):

def __init__(self, scope: Construct, construct_id: str, **kwargs) -> None:
super().__init__(scope, construct_id, **kwargs)

machine = HasMapIssueFragment(self, "Fragment 1").next(HasMapIssueFragment(self, "Fragment 2"))

self.step_function = sfn.StateMachine(
self, "The Machine",
state_machine_type=sfn.StateMachineType.STANDARD,
definition=machine,
)

app = cdk.App()
HasMapIssue(app, "HasMapIssueStack",)
app.synth()
```

### Possible Solution

_No response_

### Additional Information/Context

_No response_

### CDK CLI Version

2.54.0

### Framework Version

_No response_

### Node.js Version

v18.12.1

### OS

OSX

### Language

Python

### Language Version

Python 3.9.6

### Other information

_No response_