Unify tags for amd64 and arm64 docker images

[marcelovilla]

Context

Currently, images on dockerhub and quay have different tags for each of amd64 and arm64 architectures. For example, the 2024.11.2 tag is only available for amd64. This makes it difficult to specify a tag that should work for any of the two architectures.

For instance, in Nebari, there is a variable specifying the tag to use for conda-store. If a user wants to deploy on an architecture different from the one the image is tagged for, they must provide an override configuration with a specific tag.

I believe a potential fix would be to pass a list of target architectures in the platform input of the docker-build-push action used by the Test build Docker image and the Publish Dev Docker Images GHA worfklows instead of passing a matrix (which will trigger two different jobs).

I'm more happy to open a PR with these changes if that's helpful.

Value and/or benefit

Using the same tag for multiple architectures would simplify image tag management for users deploying conda-store on both amd64 and arm64 platforms, eliminating the need for architecture-specific overrides.

Anything else?

No response