baehyunsol ba5258d716
remove unnecessary rows in into datetime --list (#8243)
Below is the result of `into datetime --list | uniq -d`.

```
╭───┬───────────────┬─────────┬───────────────────────────────────────╮
│ # │ Specification │ Example │              Description              │
├───┼───────────────┼─────────┼───────────────────────────────────────┤
│ 0 │ %Y            │ 2023    │ The full proleptic Gregorian year,    │
│   │               │         │ zero-padded to 4 digits.              │
│ 1 │ %C            │ 20      │ The proleptic Gregorian year divided  │
│   │               │         │ by 100, zero-padded to 2 digits.      │
╰───┴───────────────┴─────────┴───────────────────────────────────────╯
```

It's supposed to be an empty table, but it has two rows. I removed the
duplicates.

# User-Facing Changes

`into datetime --list` will print out a correct table.
2023-02-27 11:21:52 +01:00
..
2022-04-20 08:50:14 -05:00
2023-02-27 20:44:05 +13:00