[Security Solution] Provide the telemetry for analyzing the search fields and TGrid columns usage for Alerts data

[YulNaumenko]

Currently we don't have the clear understanding which fields are used by the security analysts for performing filtering and data searching for the Alerts. This telemetry data could help us to keep the alert index fields to fit the user needs without the mappings explosion.

[elasticmachine]

Pinging @elastic/security-threat-hunting (Team:Threat Hunting)

[PhilippeOberti]

@YulNaumenko is that ticket still relevant or can we close it?