Windows and macOS in Actions

[iguessthislldo]

Right now I'm just testing Ubuntu 18.04 (will be 20.04 after #34). macOS and Windows would be great. There are two problems I see with this:

• I've never tested on Windows. macOS has had limited testing now even though I don't have real access to macOS. For Windows it's just that I've never sat down and tried it. After Add Functions for the OpenDDS Version, mypy, Unified Testing #34 the script for running the basic test will be in Python so that will help.

• Another problem is that right now there's no infrastructure to get OpenDDS for macOS and Windows. Right now I'm using a .deb file build and committed in https://github.com/iguessthislldo/OpenDDS-Debian. It be great if there were regular prebuilt binaries that could just be pulled in. It could be hosted somewhere in the scoreboard instead of a git repo which is less than ideal. The alternative could be building and caching OpenDDS like ACE/TAO and other dependencies are cached in the OpenDDS Actions. However this shouldn't be something PyOpenDDS should be concerned with. This could also be related to Provide OpenDDS and CMake? #29.