Add sharding key columns to web_hook_logs_daily

What does this MR do and why?

Addresses #524820

This MR precedes !215236 in order to add the sharding key columns and prepare their async indexes (exclusively on .com) because the time to create those was very large according to https://docs.gitlab.com/development/database/adding_database_indexes/#create-indexes-asynchronously.

Changelog: other

MR acceptance checklist

Evaluate this MR against the MR acceptance checklist. It helps you analyze changes to reduce risks in quality, performance, reliability, security, and maintainability.