fix: Allow explicit Provider configuration in Module

[shrink]

Closes #623

This change will enable explicit provider configuration, e.g:

provider "google" {
  alias = "service_account"

  credentials = var.service_account_credentials
}

module "project-factory" {
  providers = {
    google = google.service_account
  }

  # ...
}

I chose the version constraints (>= 3.50, < 4.0) because that is the minimum required to meet every nested module's requirements. modules/shared_vpc_access requires >= 3.43, <4.0 but 3.43 would not meet the >= 3.50, < 4.0 requirements of modules/core_project_factory.

I ran some checks and it's already not possible to use any part of this project with a version less than 3.50 because there's already an implicit dependency on >= 3.50 -- this change just makes it explicit, everything makes use of something with a dependency of >= 3.50 (including gsuite_group). Therefore, I do not believe this is a breaking change.

I reviewed the nested modules required_providers while I was doing this. Every one has a required_providers except svpc_service_project so I have added that to this PR so any provider configuration is passed through.

• svpc_service_project
• app_engine
• budget
• core_project_factory
• fabric-project
• gsuite_enabled
• gsuite_group
• project_services
• quota_manager
• shared_vpc_access

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[shrink]

@googlebot I signed it!

[comment-bot-dev]

Thanks for the PR! 🚀
✅ Lint checks have passed.

[morgante]

Please add to gsuite_enabled as well.

[shrink]

@morgante good catch! Thank you, fixed.

Re: the Actions, I am seeing one failing but I do not have permission to view the Google Cloud Build project: is there something I need to action for this to pass, or is it expected to fail when triggered by a non-collaborator?

Google Cloud Build / terraform-google-project-factory-int-trigger (cloud-foundation-cicd)

Thanks,

[morgante]

Tests are passing now, thanks!