Add support for linux/arm64 Docker image

When I ran tfupdate via Docker on my M1 Mac, the following message was output.

$ docker run -it --rm minamijoyo/tfupdate version
WARNING: The requested image's platform (linux/amd64) does not match the detected host platform (linux/arm64/v8) and no specific platform was requested

(Although this message is output, docker uses linux/amd64 Docker image and run it successfully.)

Therefore, we would like to create a linux/arm64 Docker image in GitHub Actions as well.

Test

Run .github/workflow/docker.yml on the forked branch and see the following results

GitHub Actions Workflow should exit normally
linux/arm64 image is created in kangaechu/tfupdate
Run tfupdate on M1 Mac and no warning should appear

$ docker run -it --rm kangaechu/tfupdate:add-support-for-linux-arm64-docker-image version
Unable to find image 'kangaechu/tfupdate:add-support-for-linux-arm64-docker-image' locally
add-support-for-linux-arm64-docker-image: Pulling from kangaechu/tfupdate
be307f383ecc: Pull complete
0dd357393144: Pull complete
a0f9577afe73: Pull complete
53d91f108910: Pull complete
Digest: sha256:2d764444d65ae7deefd308c070f6c8703ef38e1812ed749a90d0ea125980d552
Status: Downloaded newer image for kangaechu/tfupdate:add-support-for-linux-arm64-docker-image
Usage: tfupdate [--version] [--help] <command> [<args>]

Available commands are:
    module       Update version constraints for module
    provider     Update version constraints for provider
    release      Get release version information
    terraform    Update version constraints for terraform

minamijoyo / tfupdate

Add support for linux/arm64 Docker image #62

Test