Enable multi-platform Docker builds in GitHub Actions - Update build-…

[migueltsantana]

This commit updates the GitHub Actions workflow to support building and pushing Docker images for multiple CPU architectures using Docker Buildx.

What’s Changed

• Added docker/setup-buildx-action to enable Buildx for multi-platform builds.

• Updated docker/build-push-action to target the following platforms:

  • linux/amd64 (standard x86_64)
  • linux/arm64 (ARM64, e.g., newer Raspberry Pi)
  • linux/arm64/v8 (64-bit ARM v8 architecture)
  • linux/arm/v7 (32-bit ARM, e.g., Raspberry Pi 3 and earlier)

• Ensured the workflow pushes multi-platform images to Docker Hub.

Why This Change?

The current Docker image is only built for a single CPU architecture, which limits its usability on ARM-based devices like Raspberry Pi. By enabling multi-platform builds, Papermerge becomes more accessible and deployable across a wider range of hardware platforms, including ARM64 and ARMv8 systems, without requiring emulation.

How to Verify

• The workflow builds and pushes the Docker image for the following platforms:
  • linux/amd64
  • linux/arm64
  • linux/arm64/v8
  • linux/arm/v7
• Users on ARM and x86 systems can now pull and run the image natively.

[ciur]

@migueltsantana

Did you tried to build docker image with your changes ?
Image build is triggered when you push git tag (on your branch):

git tag 3.3b25
git push origin 3.3b25

Long story short, with your changes docker build image fails:
https://github.com/papermerge/papermerge-core/actions/runs/12400297372/job/34617134155?pr=570

Error is:

ERROR: failed to solve: python:3.13-alpine: failed to resolve source metadata for docker.io/library/python:3.13-alpine: no match for platform in manifest: not found
Error: buildx failed with: ERROR: failed to solve: python:3.13-alpine: failed to resolve source metadata for docker.io/library/python:3.13-alpine: no match for platform in manifest: not found

[migueltsantana]

Updated the file and removed "arm/v5" that was causing conflicts when sourcing Node and Python base images.

[migueltsantana]

@ciur I did build on my end, but just copy and pasted the PR into the browser instead of doing the PR inside the terminal.

However, from the full logs I saw that the "arm/v5" was a typo and should not be there. Fixed that.