Add multi-architecture support with Docker Buildx

[faehndrichm]

Summary

Adds multi-architecture build support for Linux Docker images.

This update modifies the build process so Docker images can be built and published for multiple CPU architectures ( linux/amd64, linux/arm64 and linux/arm/v7).

References

Related Issue: #34

Submitter checklist

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• Test coverage that demonstrates that the change works as expected
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