cm: Added individual Card Maker version and maimai DX passes working

core/data/schema/versions/SDEZ_4_rollback.sql

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+ALTER TABLE mai2_item_card 
+    CHANGE COLUMN startDate startDate TIMESTAMP DEFAULT "2018-01-01 00:00:00.0",
+    CHANGE COLUMN endDate endDate TIMESTAMP DEFAULT "2038-01-01 00:00:00.0";

core/data/schema/versions/SDEZ_5_upgrade.sql

@@ -0,0 +1,3 @@
+ALTER TABLE mai2_item_card 
+    CHANGE COLUMN startDate startDate TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP,
+    CHANGE COLUMN endDate endDate TIMESTAMP NOT NULL;