TT#25451 add ngcp.timezone table

* ngcp.timzone table contains the
      timezone value from config.yml
      general.timezone

Change-Id: Icbf6805bbdd0469aff863e063044994fabf9e00b

db_scripts/diff/15373.down

@@ -0,0 +1,4 @@
+USE billing;
+
+DROP TABLE ngcp.timezone;
+

db_scripts/diff/15373.up

@@ -0,0 +1,9 @@
+USE billing;
+
+CREATE TABLE ngcp.timezone
+(
+    id enum('1') not null primary key,
+    name varchar(255) not null,
+    created_at timestamp default current_timestamp,
+    modified_at timestamp default current_timestamp on update current_timestamp
+);