ubuntu: Add libcap2-bin for capsh

[travier]

Fixes: #73

[Jmennius]

Should we put it into the container file itself since it is essential to the image (not just extra)?

[travier]

This file is used during the container build to include the package in the container.

[travier]

https://github.com/toolbx-images/images/blob/main/ubuntu/18.04/Containerfile#L28

[debarshiray]

Confirmed, this fixes #73 for me.

[Jmennius]

This file is used during the container build to include the package in the container.

What I mean is - add it directly to the Containerfile - same install command but explicitly on the command line there.
Because packages listed in extra-packages are supposed to be 'extra' as the name suggests (i.e. optional) and one can expect to clean this file and the image to still be functional (which it won't be, without capsh).

[travier]

We don't split between "mandatory" and "extra" packages as far as I know.

[travier]

Feel free to make a PR to create that split :)

[Jmennius]

We don't split between "mandatory" and "extra" packages as far as I know.

I consider whatever we install in the Containerfile to be required for the image to function, by this logic - there is a split already :) For example, ubuntu-minimal, ubuntu-standard and libnss-myhostname installed there are mandatory.

[Jmennius]

Opened #75 which reverts this partially (not the sort).

[debarshiray]

For example, ubuntu-minimal, ubuntu-standard and libnss-myhostname installed there are mandatory.

The Git history says that /usr/local/sbin/unminimize, ubuntu-minimal and ubuntu-standard were removed from ubuntu-toolbox:18.04 in commit 5cbaecde2f30ea1d to fix the build.

[Jmennius]

For example, ubuntu-minimal, ubuntu-standard and libnss-myhostname installed there are mandatory.

The Git history says that /usr/local/sbin/unminimize, ubuntu-minimal and ubuntu-standard were removed from ubuntu-toolbox:18.04 in commit 5cbaecde2f30ea1d to fix the build.

I'm curious what happened there.. but it has worked before that and it works now (unminimizing and installing ubuntu-minimal and ubuntu-standard metapackages; plus other container are just like this). Hopefully it was just an intermittent failure...