New comment by sgn on void-packages repository

https://github.com/void-linux/void-packages/issues/35715#issuecomment-1170205783

Comment:
This is not a bug of `tzutils` or `tzdata`.
It's different in implementation of libc.
On a glibc system:
```sh
$ TZ=right/UTC date -d 'Dec 31 2008 23:59:60'
Wed Dec 31 11:59:60 PM UTC 2008
```

On a musl system:
```sh
$ date --debug -d 'Dec 31 2008 23:59:60'
date: parsed date part: (Y-M-D) 2022-12-31
date: parsed number part: year: 2008
date: parsed time part: 23:59:60
date: input timezone: TZ="right/UTC" environment value
date: using specified time as starting value: '23:59:60'
date: error: invalid date/time value:
date:     user provided time: '(Y-M-D) 2008-12-31 23:59:60'
date:        normalized time: '(Y-M-D) 2009-01-01 00:00:00'
date:                                  ---- -- -- -- -- --
date:      possible reasons:
date:        invalid day/month combination;
date:        numeric values overflow;
date:        missing timezone
date: invalid date ‘Dec 31 2008 23:59:60’
```

IOW, this is the musl specific behavior.