Workflow Tags are not updated

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I have created two workflows with the SDK.
Later I wanted to update the workflows using the SDK and adding tags.
I provided a list of tags in the constructor, but when viewing the workflow in the AWS UI I do not see any tags on my workflows.

### Reproduction Steps

```python
import stepfunctions
from stepfunctions.workflow import Workflow
from stepfunctions.steps import *

workflow_execution_role = ""
hello_workflow_name='hello_workflow'
hello_step = Pass(state_id="HelloWorld")

# creating a demo workflow
hello_workflow = Workflow(
name=hello_workflow_name,
definition=hello_step,
role=workflow_execution_role
)
hello_workflow_arn = hello_workflow.create()

# now trying to update the existing workflow with tags
hello_workflow_update = Workflow(
name=hello_workflow_name,
definition=hello_step,
role=workflow_execution_role,
state_machine_arn = hello_workflow_arn,
tags=[
{"key": "Environment", "value": 'example'},
{"key": "Owner", "value": 'Lasdem'},
]
)
hello_workflow_update.update(hello_step)
```

### What did you expect to happen?

I tried to add tags to an existing workflow

### What actually happened?

No Tags appeared after the update of the workflow.

### Environment

- **AWS Step Functions Data Science Python SDK version :** 2.3.0
- **Python Version:** Python 3.8.13

### Other

---

This is :bug: Bug Report

Start with the Python SDK's Workflow constructor and update() path, using the provided reproduction to compare create() with updating an existing state machine. Trace how the tags list is handled during update, then verify completion in the AWS UI by confirming the two tags appear on the workflow.

Written by the indexing model from the issue text.