Enable arm images with Docker

[bdovaz]

@ahmadnassri I use a self hosted runner (Raspberry Pi) but I can't use it with this docker image because it's only published with linux/amd64 platform:

https://hub.docker.com/r/ahmadnassri/action-dependabot-auto-merge/tags

I suppose that you can also push it with linux/arm/v7 because you rely on:

https://hub.docker.com/layers/node/library/node/alpine/images/sha256-3578f30580a34df5aba2db0a55f72aeae3c5bc572ca657ea260639be35e36996?context=explore

This image supports:

• linux/arm/v6
• linux/arm/v7
• linux/arm64/v8

So your image should also support this.

More information:

https://docs.docker.com/desktop/multi-arch/

Example:

docker buildx build --platform linux/amd64,linux/arm64,linux/arm/v7 -t username/demo:latest --push .

[bdovaz]

I have just created a PR