feat: Updates for TF 0.13

[bharathkkb]

fixes #238 #226

• Bumped versions across modules where necessary for TF0.13 compat
• Updated CI images

Todo:

• feat: relax tf version to allow 0.13 terraform-google-bootstrap#67

[daniel-cit]

The Makefile also has a reference to the developer tools image,

terraform-example-foundation/Makefile

Line 21 in cd42805

DOCKER_TAG_VERSION_DEVELOPER_TOOLS := 0

but using version 0 which today is equivalent to 0.13, 0.13.22,
which makes a make docker_test_lint, with a new developer tools image download, fails in the master branch with:

Error: Unsupported Terraform Core version

  on .terraform/modules/project/terraform-google-project-factory-8.0.1/modules/project_services/versions.tf line 18, in terraform:
  18:   required_version = "~> 0.12.6"

[bharathkkb]

@daniel-cit yeah I lock it to latest 0.12.x in this PR #250

[bharathkkb]

@rjerrems this is ready for review

[rjerrems]

Do you think it might be worthwhile continuing to support terraform > 0.12.6 until we start using terraform 0.13 features?

[rjerrems]

Overall LGTM, only thing is whether or not we should continue supporting > 0.12.6 for the time being given most of the users of the foundation will be on those versions right now. I'm open to either way, let me know what you think

[bharathkkb]

@rjerrems I was debating this as well. The only reason I kept it >=0.13 is because our next item is to try conditional modules for jenkins/CB

[rjerrems]

Perhaps we can do the development on the develop branch, then cut a release once we have adding 0.13 support / conditional modules?

[bharathkkb]

@rjerrems sgtm, I have switched the base :)

[rjerrems]

LGTM