Add new option -A is added to tools/testbuild.sh that will take the
created build executable and store it in a folder for the config
that generated it under $ARTIFACTDIR which can be set via an
environment variable or defaulted to $(TOPDIR)/buildartifacts
This is also helpful for local testing because you can now run
tools/testbuild.sh -A sim.dat and have all of the simulation
targets generated without having to rebuild along the way.
In the GitHub Actions workflow the artifacs are uploaded
two two bundles one for macOS and one for Linux
Signed-off-by: Brennan Ashton <bashton@brennanashton.com>
