It turned out previous versions of runner images were unable to run actions that require `AGENT_TOOLSDIRECTORY` or `libyaml` to exist in the runner environment. One of notable examples of such actions is [`ruby/setup-ruby`](https://github.com/ruby/setup-ruby).
This change adds the support for those actions, by setting up AGENT_TOOLSDIRECTORY and installing libyaml-dev within runner images.
Yusuke Kuoka
Reinier Timmer
Juho Saarinen