Simplify test with fewer boxes

tests/integration_test.rs

@@ -53,14 +53,7 @@ fn select_where_in() {
 
     qb.from("test").where_in(
         "foo",
-        vec![
+        vec![0, 1, 2, 3, 4, 5],
-            Box::new(0),
-            Box::new(1),
-            Box::new(2),
-            Box::new(3),
-            Box::new(4),
-            Box::new(5),
-        ],
     );
 
     let sql = qb.get_compiled_select();