Add index to partitioned web_hook_logs (Part 1 of 3)

What does this MR do?

Related issue: #323676 (closed)

We have split !59190 (closed) to three MRs as there is considerable overhead to add each index to each partition of web_hook_logs. For more information and a full analysis, check !59190 (closed)

In this MR we are adding the index on (created_at, web_hook_id) to the partitioned web_hook_logs (web_hook_logs_part_0c5294f417)

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