Updated release workflow to use imagetools so that all platforms have release tags added

[Zozman]

This PR refactors the release pipeline so that the latest and version tags are applied to both the amd64 and arm64 builds because as is only the image matching the worker's platform will have the additional tags added.

[Copilot]

Pull Request Overview

This PR refactors the release workflow to use Docker Buildx imagetools for tagging multi-platform images, ensuring that both amd64 and arm64 architectures receive the latest and version tags instead of only the platform matching the GitHub Actions runner.

Key Changes

• Replaced manual Docker pull/tag/push commands with docker buildx imagetools create commands
• Updated the re-tagging process to preserve multi-platform manifests for both architectures
• Modified echo message to clarify the multi-platform nature of the operation

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