Clean naming suggestions for Redis HLL events

What does this MR do?

• Remove old format for naming suggestions for Redis HLL events
• Remove suggested top level key license as we direct all other metrics in top level key settings
• Link to Metric Naming doc page
• Update some of the examples with new naming convention
• Open follow-up issue to update all examples we have in docs

Screenshots (strongly suggested)

Does this MR meet the acceptance criteria?

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