Proposal for Redis slots name for events tracked using Redis HLL

What does this MR do?

Add Redis slots name suggestions in Usage Ping Guide

Screenshots (strongly suggested)

Does this MR meet the acceptance criteria?

Conformity

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• Documentation (if required)
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• Separation of EE specific content

Availability and Testing

• Review and add/update tests for this feature/bug. Consider all test levels. See the Test Planning Process.
• Tested in all supported browsers
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Security

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• The MR includes necessary changes to maintain consistency between UI, API, email, or other methods
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Related to #327670 (closed)