0.0.3: Make aarch64 an alias of arm64

WORKSPACE setup

load("@bazel_tools//tools/build_defs/repo:http.bzl", "http_archive")
http_archive(
    name = "platforms",
    urls = [
        "https://mirror.bazel.build/github.com/bazelbuild/platforms/releases/download/0.0.3/platforms-0.0.3.tar.gz",
        "https://github.com/bazelbuild/platforms/releases/download/0.0.3/platforms-0.0.3.tar.gz",
    ],
    sha256 = "460caee0fa583b908c622913334ec3c1b842572b9c23cf0d3da0c2543a1a157d",
)