[tz] localized date without time

[Paul Eggert]

On 2024-07-31 18:49, Paul Eggert via tz wrote:
> You can use a format like "2023-09-20T00:000-07:00" to follow the letter 
> of the standard. I would suggest, though, using the format "2023-09-20 
> -0700"

Ooops, sorry, that first string had an extra "0". It should have been 
"2023-09-20T00:00-07:00". An inadvertent mistake, which as it happens 
underscores how unreadable that string is.