Typo: search field needs a comma

What does this MR do and why?

Adds the missing comma in the series.

Screenshots or screen recordings

before	after

How to set up and validate locally

• launch the review app
• Go to the Admin / Overview / Users section and look at the search bar

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.