Fix changelog entry for 6.4.0

What does this MR do?

This MR fixes an incorrect changelog entry that was added by Add CS_IGNORE_STATUSES setting, implement for T... (!2918 - merged)

What are the relevant issue numbers?

Allow filtering of container scan findings wher... (gitlab-org/gitlab#423954 - closed)

Does this MR meet the acceptance criteria?

• [-] Changelog trailer added
• Documentation created/updated for GitLab EE, if necessary
• Documentation created/updated for this project, if necessary
• Documentation reviewed by technical writer or follow-up review issue created
• Tests added for this feature/bug
• Job definition updated, if necessary
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• Conforms to the code review guidelines
• Conforms to the Go guidelines
• Security reports checked/validated by reviewer