This PR ramps up automated testing in preparation for the next release. It makes the following changes:
Switches from foo-latest labels to version-specific labels.
Adds additional tests on ubuntu-20.04, macos-11, and windows-2019 runners
Switches the lua version on the Ubuntu target to 5.3, since both versions of Ubuntu have that package. If it's important to test on 5.4 then I can just split up the Ubuntu job into two jobs.
This PR ramps up automated testing in preparation for the next release. It makes the following changes:
foo-latestlabels to version-specific labels.ubuntu-20.04,macos-11, andwindows-2019runners