Time::Local test failures on pre-5.30 builds for 2020

[zakame]

cf Perl/perl5#17410

Will need to add patches for images prior to Perl 5.28 5.30.

[zakame]

Note that this only affects Perls out of the current supported versions (that is, everything before 5.28.) from 5.28 and previous releases. Official Docker images for versions before 5.26 are still available but not updated anymore (i.e. not getting security updates from their debian or buildpack-deps base image) but we here will consider supplying patches in the tree for anyone else who cares to do image rebuilds on their own.

As for 5.26 and 5.28, it will be updated with a patch for rebuild and official release.

[zakame]

https://rt.cpan.org/Public/Ticket/Attachment/1776857/956088/0001-Fix-Time-Local-tests.patch seems to be working for this.

[zakame]

Further testing seems to show that the patch only applies for perls 5.26 and up. Will need to check for earlier versions.

[zakame]

Based on https://github.com/docker-library/official-images/blob/d57621357f947aeebd68c9057895d51d2c5f1a14/library/perl we expect 5.26 images to be rebuilt as well.

[zakame]

Updated 5.26 and 5.28 images are published now. 🎉

Will keep this issue open for a few more days until I figure how to backport the Time-Local patch to older perls (or not.)