Fix displaying wrong icon

What does this MR do and why?

Due to a typo, the icon name was always returned as success. This MR fixes that behaviour.

Screenshots or screen recordings

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How to set up and validate locally

1. You'll need an EE License
2. You'll need to have runners enabled (See $2408961 for setting up a runner)
3. Enable :refactor_security_extension to turn this feature on.

echo "Feature.enable(:refactor_security_extension)" | rails c

1. Import https://gitlab.com/gitlab-examples/security/security-reports
2. Create a new MR by editing a file
3. Go to the MR page and check the widget

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.