Introduce aarch64 Docker image

[jasontedor]

This commit introduces the infrastructure needed to build a Docker image for aarch64.

Relates #53914

[pugnascotia]

These changes look good.

I wondered whether it was worth gathering the various bits of architecture-related data into a couple of enums? E.g. (incomplete):

public enum DockerArchitecture {
    X_64("linux-x86_64", "centos:7", ""),
    AARCH_64("linux-aarch64", "arm64v8/centos:7", "-arm64");

    public final String classifier;
    public final String dockerImage;
    public final String tiniSuffix;

    DockerArchitecture(String classifier, String dockerImage, String tiniSuffix) {
        this.classifier = classifier;
        this.dockerImage = dockerImage;
        this.tiniSuffix = tiniSuffix;
    }
}