add support for TZ

[Arlind-dev]

This PR adds the tzdata package, allowing you to set your Timezone using the TZ variable.

It fixed my Timezone issues (tested this locally), but feel free to close if there's a better solution, that I'm not aware of.

[diced]

Is tzdata needed? In my experience, setting the timezone on linux machines has been something like: ln -sf /usr/share/zoneinfo/America/Los_Angeles /etc/localtime (links a timezone in /usr/share/zoneinfo to /etc/localtime). If alpine doesn't include these, I guess we can add tzdata and if it also works with setting the TZ variable thats also convenient.

[diced]

guess it does work, with a quick test below:

docker run --env='TZ=America/Los_Angeles' -it alpine sh -c 'apk add --no-cache tzdata && date'

fetch https://dl-cdn.alpinelinux.org/alpine/v3.21/main/x86_64/APKINDEX.tar.gz
fetch https://dl-cdn.alpinelinux.org/alpine/v3.21/community/x86_64/APKINDEX.tar.gz
(1/1) Installing tzdata (2024b-r1)
OK: 7 MiB in 16 packages
Thu Jan  9 12:01:10 PST 2025

without tzdata it goes to utc:

docker run --env='TZ=America/Los_Angeles' -it alpine date

Thu Jan  9 20:02:19 UTC 2025