Add support to install nerdctl and buildkit with the alpine-iso template

[jandubois]

All 3 binaries are now available in Alpine 3.17, from buildctl and buildkit <sic> and nerdctl apks.

Will make a separate PR to make the setuid chmod optional, to require using sudo with nerdctl...

Originally posted by @afbjorklund in lima-vm/alpine-lima#77 (comment)

[jandubois]

I've only created this issue because I want to close lima-vm/alpine-lima#77.

I'm not sure if we care about supporting containerd.system: true for Alpine (although the code would then also work for the regular non-ISO image.

I'm also fine with closing this issue and leaving it to the user to install additional packages via provisioning scripts.

[afbjorklund]

I'm also fine with closing this issue and leaving it to the user to install additional packages via provisioning scripts.

That is OK with me, the original issue was only to split the installation in the ISO into the same three components...

[afbjorklund]

I think the nerdctl containerd-rootless-setuptool.sh script had some issues, when trying to run it outside of systemd.

• Systemd requirement for running rootless containers #310

[AkihiroSuda]

containerd-rootless-setuptool.sh is dedicated for systemd, but containerd-rootless.sh should work without it
(haven't tried with Alpine)