Build broken by change in GitHub source ZIP generation

@stefanbucur In the last 12 hours, something changed in the way GitHub generates git archive ZIPs, which causes the build to fail due to checksum mismatches. This affects all users that do not currently have this dependency cached in their repository cache. For the full context, see https://github.com/bazel-contrib/SIG-rules-authors/issues/11.

I filed a ticket with GitHub, but am unsure about what we should do in the meantime. TAR archives appear to be unaffected by the change, but I also wouldn't have expected ZIP archives to ever change. For example abseil doesn't publish their own release archives and exclusively relies on tags and the GitHub-generated files.