chore: improve scenes deployment

[charly-bg]

• The deploy workflow now filters and processes only the scenes that actually had changes. This applies to PRs, pushes, and manual runs
• Follow-up steps like export, S3 upload, and asset bundle conversion are all conditional now, so nothing runs if there aren’t any updated scenes
• Updated the git checkout step to fetch the full history, which fixes some issues with the change detection logic
• Also cleaned up the README in advanced-avatar-swap to trigger the execution of steps related to scenes changed

[github-actions]

Test this pull request

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  /goto https://sdk-team-cdn.decentraland.org/ipfs/goerli-plaza-chore-improve-scenes-deploy-latest

This PR has been published using the @dcl/sdk version @dcl/sdk@latest

[nachomazzara]

LGTM