Add provider config organization, making all resource organization fields optional

[brandonc]

Description

Drawing inspiration from the google provider, this adds a new provider config field organization which could make all the resource-specific organization fields optional if defined. Please review commit-wise

Testing plan

My testing methodology was making sure that config can be refactored from resource-specific org to default org with no infrastructure changes and vice-versa.

Example Config

The config contains all the resources that previously required an organization field:

provider "tfe" {
  hostname = "..."
  token = "..."
  organization = "hashicorp"
}

variable "gh_token" {
  type = string
}

variable "ssh_key" {
  type = string
}

resource "tfe_workspace" "foo" {
  name = "foo"
}

resource "tfe_variable_set" "foo" {
  name          = "Test Varset"
  description   = "Some description."
}

resource "tfe_workspace_variable_set" "foo" {
  workspace_id    = tfe_workspace.foo.id
  variable_set_id = tfe_variable_set.foo.id
}

resource "tfe_variable" "test-a" {
  key             = "seperate_variable"
  value           = "my_value_name"
  category        = "terraform"
  description     = "a useful description"
  variable_set_id = tfe_variable_set.foo.id
}

resource "tfe_agent_pool" "foo" {
  name         = "my-agent-pool-name"
}

resource "tfe_oauth_client" "foo" {
  name             = "my-github-oauth-client"
  api_url          = "https://api.github.com"
  http_url         = "https://github.com"
  oauth_token      = var.gh_token
  service_provider = "github"
}

resource "tfe_organization_membership" "test1" {
  email = "example1@company.com"
}

resource "tfe_organization_membership" "test2" {
  email = "example2@company.com"
}

resource "tfe_organization_token" "test" {
  force_regenerate = true
}

resource "tfe_policy" "test" {
  name         = "my-policy-name"
  description  = "This policy always passes"
  kind         = "sentinel"
  policy       = "main = rule { true }"
  enforce_mode = "hard-mandatory"
}

resource "tfe_policy_set" "test" {
  name          = "my-policy-set"
  description   = "A brand new policy set"
  kind          = "sentinel"
  policy_ids    = [tfe_policy.test.id]
  workspace_ids = [tfe_workspace.foo.id]
}

resource "tfe_project" "test" {
  name = "projectname"
}

resource "tfe_ssh_key" "test" {
  name         = "my-ssh-key-name"
  key          = var.ssh_key
}

resource "tfe_team" "test" {
  name         = "my-team-name"
}

data "tfe_agent_pool" "test" {
  name          = "my-agent-pool-name"
}

output "agent-pool" {
  value = data.tfe_agent_pool.test.id
}

External links

Closes #434

[Uk1288]

Looking good, I was able to smoke test the default org 🎉

One comment, It might be helpful to indicate on the doc that when using default_organization, the organization must already exist, unlike when an org is specified with a resource block. Consequently, the organization must be a literal and cannot be resource/datasource instance like resource.tfe_organization.test-org.name.

[brandonc]

@Uk1288 I fixed a bug in the tfe_outputs data source and added alternative configuration using TFE_ORGANIZATION environment variable.

[Uk1288]

LGTM 🎉