✨ [RUM-139] use trusted types policy

[BenoitZugmeyer]

Motivation

#3506

Changes

• Configure Webpack to use the datadog-chunk Trusted Type policy to load chunks
• Use the datadog-worker Trusted Type policy to load the compression worker

Thoughts

Ideally we would use the same policy for both, but:

• the Webpack runtime is creating the policy internally and does not expose it anywhere, so we cannot reuse it
• we cannot use the same name for both policies, because by default it's not allowed to create duplicated policies (see doc)

Test instructions

Checklist

• Tested locally
• Tested on staging
• Added unit tests for this change.
• Added e2e/integration tests for this change.