Eliminate hardcoding of business_unit (1 & 2) in 4-Projects

[mromascanu123]

TL;DR

• why hardcoded rather than passed via global config via their parameters
• why subnet_ip_range hardcoded?

Terraform Resources

No response

Detailed design

Provide configurations via top-level global config or at least tfvar-based at the package level

Additional information

No response

[fmichaelobrien]

stale bot timer restart - https://github.com/terraform-google-modules/terraform-example-foundation/blob/master/.github/workflows/stale.yml#L21

[sleighton2022]

Closing. Our working principal is that this is example code, and not a module. If something needs to be put in place only once, we won't create a variable. If something is used in multiple places, we will use a variable. May be fixed in #1226