chore: rename fields for elastic

[ktechmidas]

Issue being fixed or feature implemented

Issue of consistency with tenderdash fixed

What was done?

Renamed json.span.height to json.height and json.span.round to json.round in elastic for consistency with Tenderdash

How Has This Been Tested?

N/T

Breaking Changes

None

Checklist:

• [ ] I have performed a self-review of my own code
• [ ] I have commented my code, particularly in hard-to-understand areas
• [ ] I have added or updated relevant unit/integration/functional/e2e tests
• [ ] I have made corresponding changes to the documentation

For repository code-owners and collaborators only

• [ ] I have assigned this pull request to a milestone

[strophy]

@ktechmidas please test this and verify logs are received in a useful format