fix: reusable-docker-build-publish caching

[erikburt]

Changes

• Adds default cache-to and cache-from values
• Compute a relevant cache scope based on dockerfile path, custom tag suffixes, and runner os/arch
• Adds S3 cache setup (this no-ops for GH-hosted runners)

Testing

• test: docker-build caching chainlink#23144
• Got as fast as 5m19s in the best case scenario: https://github.com/smartcontractkit/chainlink/actions/runs/29467579485

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DX-4666