making-your-first-query.ipynb compatible with Google Colab

[solver-Mart1n]

Thank you, @ploomber, for the python notebook, making-your-first-query.ipynb. It is very useful as an introduction to SQL and relational databases. It allows the user to interact with the database using SQL queries with the ease of a Jupyter notebook.

To enhance the user-friendliness of the Python notebook, I ran it on Google Colab. And found the following error during execution of the following code cell:

The ModuleNotFoundError: No module named 'banking' is due to a missing dependency, which is the banking.py module.

To remedy this issue when running on Google Colab, I initiate a pull request of my https://github.com/solver-Mart1n/sql/tree/GoogleColab-port branch.