improving the parametrization tutorial

[edublancas]

We recently introduced a new way to parameterize SQL queries: https://jupysql.ploomber.io/en/latest/user-guide/template.html

However, the tutorial is pretty short. We should improve it to make it more compelling to show how users can benefit from parametrized SQL queries. For inspiration, we can look at dbt docs, which also use jinja2 for parametrization (although some features might not work here)

[neelasha23]

Acceptance Criteria:

1. Research on usecases of parametrized SQL queries
2. Review dbt docs.
3. Improve tutorial by adding more examples/ usecases.
4. Changelog entry