CLOUDP-323996: Fix make multiarch image

[josvazg]

Summary

This fixes the Makefile to produce multi-arch images, just like the CI already does:

1. Create a multiarch-builder buildx builder configured to support multi architecture builds.
2. Build & push using multiarch-builder buildx builder for all target platforms at once.

Proof of Work

Command make image VERSION=... produced a proper prerelease multi-archi image as expected.

Checklist

• Have you linked a jira ticket and/or is the ticket in the title?
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[igor-karpukhin]

LGMT with one nit: the image target is also used for local builds. So, I'd create a new one image-multiarch and make our CI to use it, since we don't need a multiarch image for local tests

[josvazg]

LGMT with one nit: the image target is also used for local builds. So, I'd create a new one image-multiarch and make our CI to use it, since we don't need a multiarch image for local tests

yes, I will leave the image target as it was and move the fix to a new key image-multiarch: as suggested