TEMPORARY: remove native token cofniguration for staging

[AmbientTea]

Description

This PR removes the native token configuration form the staging chain spec so the observability stays inert at the beginning. This is a temporary change for testing purposes.

Checklist

• Commit sequence broadly makes sense and commits have useful messages.
• New tests are added if needed and existing tests are updated.
• Relevant logging and metrics added
• CI passes. See note on CI.
• Any changes are noted in the changelog.md for affected crate
• Self-reviewed the diff

Note on CI

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