CLOUDSTACK-10117: Allow scoped setting to have nullable values (#2413)

Allows scope setting for domain_details to have nullable values.

Author: DaanHoogland

engine/schema/resources/META-INF/db/schema-41000to41100.sql

@@ -536,7 +536,7 @@ CREATE TABLE IF NOT EXISTS `cloud`.`domain_details` (
     `id` bigint unsigned NOT NULL auto_increment,
     `domain_id` bigint unsigned NOT NULL COMMENT 'account id',
     `name` varchar(255) NOT NULL,
-    `value` varchar(255) NOT NULL,
+    `value` varchar(255) NULL,
     PRIMARY KEY (`id`),
     CONSTRAINT `fk_domain_details__domain_id` FOREIGN KEY (`domain_id`) REFERENCES `domain`(`id`) ON DELETE CASCADE
 )ENGINE=InnoDB DEFAULT CHARSET=utf8;