Alpine ruby image fails Ruby TZ tests due to lack of tzdata

sudo docker run --env TZ=America/Los_Angeles -it ruby:slim /usr/local/bin/ruby -e 'puts Time.utc(2007, 11, 4, 9, 0, 0).localtime'

2007-11-04 01:00:00 -0800

sudo docker run --env TZ=America/Los_Angeles -it ruby:alpine /usr/local/bin/ruby -e 'puts Time.utc(2007, 11, 4, 9, 0, 0).localtime'

2007-11-04 09:00:00 +0000

Some searching led to this:
https://github.com/docker-library/ruby/issues/218

Pointing to this:
https://serverfault.com/questions/683605/docker-container-time-timezone-will-not-reflect-changes/683651#683651

Pointing to this:
https://github.com/gliderlabs/docker-alpine/issues/136

Which looks a LOT like this is a known issue/WONTFIX, but I must protest. This fails the ruby TZ tests.

I understand that as a minimalist distribution, Alpine, tzdata is not required, but it is required for properly-functioning ruby. If the maintainers believe that it is correct to leave tzdata out of the ruby:alpine image, then surely it is friendly to document the absence of the package, probably via a comment next to one of the apk add statements. (I would prefer it in the build set, as it is needed for the tests to pass.)

Start by reproducing the contrasting ruby:slim and ruby:alpine commands with TZ=America/Los_Angeles and compare their output. The reported Ruby TZ tests should pass for the Alpine image, or the image should clearly document that tzdata is absent; the linked discussions provide context for that decision.