Initial MVP for CI/CD (#608)

* preliminary support for wif in stage 0

* IAM wif role

* IAM wif role TODO

* add support for external SA IAM to SA module

* add name output to SA module

* separate cicd SA

* tfdoc

* GITLAB principal (untested)

* make GCS name output static

* outputs bucket

* fix stage 1 test

* tweak outputs

* tfdoc

* move wif_pool to automation variable

* add support for top-level and repository providers

* add missing boilerplate

* fix branchless principal

* initial workflow

* symlink provider template in stages

* remove service accounts from stage 0 cicd tfvars

* add cicd interface variable to resman stage

* fix cicd variable in resman stage

* better condition on outputs_location

* fix last change

* change outputs_location type

* revert outputs_location change

* split outputs in stage 0

* update ci/cd temporary notes

* rename additive IAM resource in SA module

* split outputs in stage 1

* remove unused locals

* fix stage 1 tests

* tfdoc

* Upload action files to outputs_bucket

* Fix tests and README

* rename template, streamline outputs

* local templates and gcs output for all stage 2

* add workflows to local output files

* Use lowercase WIF providers everywhere

* Bring back suffix for workflow files

* Remove unused files

* Update READMEs

* preliminary CI/CD implementation for stage 1

* fix stage 1

* stage 1 cicd

* tfdoc

* fix tests

* readme and links for cicd and wif

* refactor wif providers

* refactor cicd for stage 1

* fix stage 1

* wif org policies

* split identity provider configuration from cicd

* add type attribute to cicd repositories

* valid cicd repositories have a workflow template

* refactor stage 01

* fix stage 01 tests

* minimal CI/CD documentation

* better check_links error reporting

* fix links

* Added Gitlab specific configurations

Set the default issuer_uri for Gitlab. Added allowed audiences to OIDC configuration.

* Fixed TF formatting in identity providers.

* Changing identity provider audience to null

Changing identity provider audience to default to null.

* add instructions for renaming workflows

* address Julio's comments

Co-authored-by: Julio Castillo <jccb@google.com>
Co-authored-by: alexmeissner <alexmeissner@google.com>

tests/fast/stages/s01_resman/fixture/main.tf

@@ -15,8 +15,13 @@
  */
 
 module "stage" {
-  source                = "../../../../../fast/stages/01-resman"
-  automation_project_id = "fast-prod-automation"
+  source = "../../../../../fast/stages/01-resman"
+  automation = {
+    federated_identity_pool      = null
+    federated_identity_providers = null
+    project_id                   = "fast-prod-automation"
+    outputs_bucket               = "test"
+  }
   billing_account = {
     id              = "000000-111111-222222"
     organization_id = 123456789012

tests/fast/stages/s02_networking_nva/fixture/main.tf

@@ -17,6 +17,9 @@
 module "stage" {
   source   = "../../../../../fast/stages/02-networking-nva"
   data_dir = "../../../../../fast/stages/02-networking-nva/data/"
+  automation = {
+    outputs_bucket = "test"
+  }
   billing_account = {
     id              = "000000-111111-222222"
     organization_id = 123456789012

tests/fast/stages/s02_networking_peering/fixture/main.tf

@@ -17,6 +17,9 @@
 module "stage" {
   source   = "../../../../../fast/stages/02-networking-peering"
   data_dir = "../../../../../fast/stages/02-networking-peering/data/"
+  automation = {
+    outputs_bucket = "test"
+  }
   billing_account = {
     id              = "000000-111111-222222"
     organization_id = 123456789012

tests/fast/stages/s02_networking_vpn/fixture/main.tf

@@ -17,6 +17,9 @@
 module "stage" {
   source   = "../../../../../fast/stages/02-networking-vpn"
   data_dir = "../../../../../fast/stages/02-networking-vpn/data/"
+  automation = {
+    outputs_bucket = "test"
+  }
   billing_account = {
     id              = "000000-111111-222222"
     organization_id = 123456789012

tests/fast/stages/s02_security/fixture/main.tf

@@ -16,6 +16,9 @@
 
 module "stage" {
   source = "../../../../../fast/stages/02-security"
+  automation = {
+    outputs_bucket = "test"
+  }
   billing_account = {
     id              = "000000-111111-222222"
     organization_id = 123456789012