Docker allows to set up a portable development environment in a container. This
can be useful to test Linux toolchains on macOS. Introduce such environments
for EDK II and documentation development.
The current implementation supports both Dev Environments by Docker Desktop and
Dev Containers by Visual Studio Code. To reduce the maintenance burden, use
these environments for the Linux-based GitHub Actions as well. Non-x86 hosts,
including Apple Silicon, are supported via GCC cross-compilation.
