feat: build multiarch Docker images

[kuisathaverat]

it builds the base image for linux/amd64 and linux/arm64, the push is delegated to buildx, this push the manifest for the two platforms

related to #153

[mergify]

This pull request does not have a backport label. Could you fix it @kuisathaverat? 🙏
To fixup this pull request, you need to add the backport labels for the needed
branches, such as:

• backport-v./d./d is the label to automatically backport to the 1./d branch. /d is the digit
  NOTE: backport-skip has been added to this pull request.

[elasticmachine]

💚 Build Succeeded

the below badges are clickable and redirect to their specific view in the CI or DOCS

Expand to view the summary

Build stats

• Start Time: 2022-05-16T10:23:05.584+0000

• Duration: 36 min 6 sec

🤖 GitHub comments

To re-run your PR in the CI, just comment with:

• /test : Re-trigger the build.

[kuisathaverat]

/test

[v1v]

required?

[kuisathaverat]

I need to give a second round on this, but in a follow up PR, because of that it si commented.