### Describe the issue with documentation

`BaseOperator` type hints for `retry_delay` and `max_retry_delay` shows `timedelta` only, however the params also accept `float` seconds values.
Also, type hint for `dag` param is missing.
More precise type hints and params descriptions in the docs can help to understand the code behavior easier.

### How to solve the problem

_No response_

### Anything else

_No response_

### Are you willing to submit PR?

- [X] Yes I am willing to submit a PR!

### Code of Conduct

- [X] I agree to follow this project's [Code of Conduct](https://github.com/apache/airflow/blob/main/CODE_OF_CONDUCT.md)

airflow/models/baseoperator.py
"""Stringified DAGs and operators contain exactly these fields."""
        if not cls.__serialized_fields:
            from airflow.models.dag import DagContext
            
            
            
            
            DagContext.push_context_managed_dag(None)
            cls.__serialized_fields = frozenset(
                vars(BaseOperator(task_id='test')).keys()
                - {
                    'inlets',
                    'outlets',