Simepl tutorial Dags are polished

### Description

As described in https://cwiki.apache.org/confluence/display/AIRFLOW/Examples+Refurbish

The simple tutorial Dags are planned to be kept - but they also should be re-worked according to new quality standard so they are matching to best practices.

### Use case/motivation

_No response_

### Related issues

_No response_

### Are you willing to submit a PR?

- [ ] 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)

Start by reading the linked Examples Refurbish guidance, then inspect the simple tutorial DAGs in the Airflow repository and compare them with the stated quality standards. Done means the retained tutorial DAGs have been reworked to follow those best practices.

Written by the indexing model from the issue text.