Terraform initial database.

This addes TF config for creating the initial database for the selected
ATAT environment. The datatase name format is [environment]-atat.

terraform/modules/postgres/main.tf

@@ -34,4 +34,12 @@ resource "azurerm_postgresql_virtual_network_rule" "sql" {
   server_name                          = azurerm_postgresql_server.sql.name
   subnet_id                            = var.subnet_id
   ignore_missing_vnet_service_endpoint = true
-}
+}
+
+resource "azurerm_postgresql_database" "db" {
+  name                = "${var.environment}-atat"
+  resource_group_name = azurerm_resource_group.sql.name
+  server_name         = azurerm_postgresql_server.sql.name
+  charset             = "UTF8"
+  collation           = "en_US.utf8"
+}

terraform/modules/postgres/outputs.tf

@@ -0,0 +1,3 @@
+output "db_name" {
+  value = azurerm_postgresql_database.db.name
+}