Fixing key warning

Author: James Cori

src/components/ChallengeEditor/ChallengeView/index.js

@@ -165,7 +165,7 @@ const ChallengeView = ({
             )}
             <div>
               { challenge.discussions && challenge.discussions.map(d => (
-                <div className={cn(styles.row, styles.topRow)}>
+                <div key={d.id} className={cn(styles.row, styles.topRow)}>
                   <div className={styles.col}>
                     <span><span className={styles.fieldTitle}>Forum:</span> <a href={d.url} target='_blank' rel='noopener noreferrer'>{d.name}</a></span>
                   </div>