#714 - update postgres version for tests

BudgetMasterServer/src/test/java/de/deadlocker8/budgetmaster/TestConstants.java

@@ -7,5 +7,5 @@ public class TestConstants
 		// empty
 	}
 
-	public static final String POSTGRES_VERSION = "postgres:14.5";
+	public static final String POSTGRES_VERSION = "postgres:15.1";
 }