Maintenance "Any" option isn't supported

[mnacharov]

TL;DR

I'm pretty agnostic about the time windows for my dev databases with a db-f1-micro machine type. It would be great to be able to set "Any" upgrade window for them.

Also, it looks better to me to have it by default, don't you think?

Expected behavior

In case, I didn't specify maintenance_window_day nor maintenance_window_hour, or manually specified them to 0, do not pass settings.maintenance_window to the google provider at all, which will mean "Any" maintenance window.

Observed behavior

not possible to not pass settings.maintenance_window, setting maintenance_window_hour and maintenance_window_day to 0 lead to validation error:

│ Error: expected settings.0.maintenance_window.0.day to be in the range (1 - 7), got 0
│ 
│   with module.postgres.google_sql_database_instance.default,
│   on .terraform/modules/backstage/modules/postgresql/main.tf line 79, in resource "google_sql_database_instance" "default":
│   79:   settings {

Terraform Configuration

module "postgres" {
  source            = "GoogleCloudPlatform/sql-db/google//modules/postgresql"
  version           = "~> 26.2"
  name              = "postgres"
  availability_type = "ZONAL"
  database_version  = "POSTGRES_16"
  project_id        = var.project_id
  zone              = "europe-west4-a"
  region            = "europe-west4"
  tier              = "db-f1-micro"
  user_name         = "test"
  user_password     = "test"
  db_name           = "test"
  create_timeout    = "30m"

  maintenance_window_day          = 0
  maintenance_window_hour         = 0
  maintenance_window_update_track = "canary"
}

Terraform Version

Terraform v1.14.0
on darwin_arm64
+ provider registry.terraform.io/hashicorp/google v7.12.0
+ provider registry.terraform.io/hashicorp/google-beta v7.12.0
+ provider registry.terraform.io/hashicorp/null v3.2.4
+ provider registry.terraform.io/hashicorp/random v3.7.2

Terraform Provider Versions

Providers required by configuration:
.
├── provider[registry.terraform.io/hashicorp/google] ~> 7.12
├── provider[registry.terraform.io/hashicorp/google-beta] ~> 7.12
├── provider[terraform.io/builtin/terraform]
├── module.private-service-access
│   ├── provider[registry.terraform.io/hashicorp/null] ~> 3.1
│   ├── provider[registry.terraform.io/hashicorp/google] >= 5.38.0, < 8.0.0
│   └── provider[registry.terraform.io/hashicorp/google-beta] >= 5.38.0, < 8.0.0
└── module.backstage
    ├── provider[registry.terraform.io/hashicorp/google-beta] >= 6.31.0, < 8.0.0
    ├── provider[registry.terraform.io/hashicorp/null] ~> 3.1
    ├── provider[registry.terraform.io/hashicorp/random] ~> 3.1
    └── provider[registry.terraform.io/hashicorp/google] >= 6.31.0, < 8.0.0

Providers required by state:

    provider[terraform.io/builtin/terraform]

    provider[registry.terraform.io/hashicorp/google]

    provider[registry.terraform.io/hashicorp/google-beta]

    provider[registry.terraform.io/hashicorp/null]

    provider[registry.terraform.io/hashicorp/random]

Additional information

No response