Add Customer Success::Impact Check label when metric category changes

What does this MR do and why?

Add Customer SuccessImpact Check label to MR when there is a change in Operational (category) Metric definition status.

Screenshots or screen recordings

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How to set up and validate locally

Numbered steps to set up and validate the change are strongly suggested.

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.

Related to #365897 (closed)