Please add a registry: parameter

[justinmchase]

Behaviour

I have to use a corporate proxy (jfrog artifactory). This image attempts to pull from public docker hub (docker.io) by default and the way to configure an alternate registry differs from other docker actions.

The docker/login-action action has a registry parameter. This one for some reason only has an image: parameter. I was able to just alter the image value to have the full path to our internal proxy but it definitely made me stop and have to go look up the docs rather than just having all of the docker images have the same input parameters.

A couple of developers took 30m trying to figure out why the registry: parameter wasn't working like the other action only to find out they're just both different. Consistency across actions would help quite a bit!

[crazy-max]

docker/setup-buildx-action#224 (comment)