feat: build cross-platform images

[meysam81]

Related Issue or Design Document

fixes #331

This PR will build cross-platform Docker images that can be run on more than the current linux/amd64.

Here is a successful CI run:

https://app.circleci.com/pipelines/circleci/A6nbzUoyB9CLzi6DLvaBwb/9smwwFNYSRdLYqTVLve6He/13/workflows/2894361c-6b9b-48e5-8e73-641d79753ce4/jobs/23

And here is the result of that CI run, pushing to my personal Docker repository:

https://hub.docker.com/r/meysam81/kratos-selfservice-ui-node/tags

Checklist

• I have read the contributing guidelines and signed the CLA.
• I have referenced an issue containing the design document if my change introduces a new feature.
• I have read the security policy.
• I confirm that this pull request does not address a security vulnerability.
  If this pull request addresses a security vulnerability,
  I confirm that I got approval (please contact [email protected]) from the maintainers to push the changes.
• I have added tests that prove my fix is effective or that my feature works.
• I have added the necessary documentation within the code base (if appropriate).

Further comments

[aeneasr]

Awesome, thank you! 🎉 Your contribution makes Ory better :)