Add default database value

Author: CharlesDelannoy

postgresql/resource_postgresql_script.go

@@ -33,6 +33,7 @@ func resourcePostgreSQLScript() *schema.Resource {
 				Type:        schema.TypeString,
 				Optional:    true,
 				Computed:    true,
+				Default:     "postgres",
 				Description: "The database to execute commands in (defaults to provider's configured database)",
 			},
 			scriptCommandsAttr: {