ER: Use terraform.tfvar file for passing in required parameters. Including region, zone, project id etc.

### Enhancement Request Details

As an end user I want to not pass the variables in the main.tf file.

Can you please modify the code to leverage terraform.tfvar file for passing in required parameters. Including region, zone, project id etc.

### Version

latest code

### What database engine is this documentation change for?

All

### Relevant log output

_No response_