chore: use peer-lb to fetch contents from content server

[menduz]

What?

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Why?

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[github-actions[bot]]

After the CI passes:

• This branch can be previewed at https://play.decentraland.zone/branch/peer-lb/index.html
• The decentraland-ecs package can be tested in scenes by running

  npm install "https://play.decentraland.zone/branch/peer-lb/decentraland-ecs.tgz"