SUCO: apt packages that are hosted on ros.org apt source aren't installed

[130s]

This is a known design issue. The tool does not modify apt source as of 0.1, so any custom apt sources, incl. ros.org, the one I frequently use, needs to be manually added.

[130s]

Result on brya. Is this related?

Error: WARNING: ROS_PYTHON_VERSION is unset. Defaulting to 3
ERROR: the following packages/stacks could not have their rosdep keys resolved
to system dependencies (ROS distro is not set. Make sure `ROS_DISTRO` environment variable is set, or use `--rosdistro` option to specify the distro, e.g. `--rosdistro indigo`):
hut_10sqft: Cannot locate rosdep definition for [ament]
Continuing to install resolvable dependencies...
E: Unable to locate package python3-rocker
E: Unable to locate package python3-vcstool
ERROR: the following rosdeps failed to install
  apt: command [sudo -H apt-get install -y python3-rocker] failed
  apt: command [sudo -H apt-get install -y python3-vcstool] failed

Not yet understood what was going on.