Add a security section to SQL Module

Which module(s) and week(s) does this change affect?
Module(s): SQL Module
Week(s): unsure

What is the work that needs to be done?

We should add something to the module RE security using an .env file instead of the computer user

Why is this work important to do?

Currently using the computer user and I'm told this is not ideal! @MarkFarmiloe please can you add a bit of info as this is not my area of expertise!

Additional context

Who might need to know about this change?

@CodeYourFuture/syllabus-team