Change format of abuse detection logging

What does this MR do and why?

Change format of abuse detection logging

It is better for abuse.messages to be a more generic array of strings so Elasticsearch does not have to create mappings for every single field that is validated.

• This change is behind a feature flag (prevent_abusive_searches)
• Feature Flag rollout issue: #346263 (closed)

Screenshots or screen recordings

This is how logging looks like in Staging right now. See how there are multiple columns? This MR will combine all of the messages into a single column: abuse.messages from the SeachController.

How to set up and validate locally

N/A

MR acceptance checklist

This checklist encourages us to confirm any changes have been analyzed to reduce risks in quality, performance, reliability, security, and maintainability.

• I have evaluated the MR acceptance checklist for this MR.