RVRNEXT-5 add migration for currencies

database/migrations/structure/20230421_2234_currencies.sql

@@ -0,0 +1,10 @@
+CREATE TABLE `currencies` (
+  `id` int(10) unsigned NOT NULL AUTO_INCREMENT,
+  `community_id` int(10) unsigned NOT NULL,
+  `code` varchar(3) NOT NULL,
+  `round_digits` tinyint(1) unsigned NOT NULL,
+  PRIMARY KEY (`id`),
+  UNIQUE KEY `unique_currency_for_community` (`community_id`, `code`),
+  KEY `community_id` (`community_id`),
+  CONSTRAINT `currencies_community_id` FOREIGN KEY (`community_id`) REFERENCES `communities` (`id`)
+) ENGINE = InnoDB DEFAULT CHARSET = utf8mb4;