Add multi-arch container image builds

[roib20]

Following on commit 49be2f0, I decided to do additional work to try and improve the container.yml GitHub Action.

The features I added:

• Multi-arch images for all OS/ARCH that are supported by the official jellyfin/jellyfin image:
  • linux/amd64
  • linux/arm/v7
  • linux/arm64/v8
• Add automated tags for container image including latest and current semver version.
• Add checks to ensure PRs can't publish images.
• Update versions for GH Actions.
• Auto-indent YAML.

This Pull Request possibly closes issues #103 and #128.

[roib20]

This Pull Request already implements the same version bumps as dependabot's PRs #133 and #134.

[roib20]

Thank you for merging my PR. Please note, the Publish container Action needs to run again manually in order to publish the multi-arch container images.