We still run `make upload` in automation builds even though all of our builds are in taskcluster now so all it does is copy files from dist to the artifact upload directory. We should just fix things so `make package` write their artifacts directly into the artifact upload directory and stop running `make upload`. There is one thing we'd need to handle specially, which is that we generate a checksum file as part of upload currently: https://dxr.mozilla.org/mozilla-central/rev/789e30ff2e3d6e1fcfce1a373c1e5635488d24da/toolkit/mozapps/installer/packager.mk#161 We could just make the checksum file depend on all the package artifacts and run it as the last thing in `make package` instead.