Fixed multiplatform builds for docker images in pipeline

[behackl]

Overview: What does this pull request change?

Follow-up to #2701, simplifies workflow by building both arm and amd images on one machine. Makes docker-buildx work properly.

Motivation and Explanation: Why and how do your changes improve the library?

Links to added or changed documentation pages

Further Information and Comments

Reviewer Checklist

• The PR title is descriptive enough for the changelog, and the PR is labeled correctly
• If applicable: newly added non-private functions and classes have a docstring including a short summary and a PARAMETERS section
• If applicable: newly added functions and classes are tested

[naveen521kk]

LGTM! I previously thought that we could use the native arm64 runners from Oracle to build the images but seems like it creates issues and using buildx should work I guess.