TCA-1067 - fix sidebar label

Author: vas3a

src-ts/tools/learn/certification-details/certification-details-sidebar/CertificationDetailsSidebar.tsx

@@ -115,7 +115,7 @@ const CertificationDetailsSidebar: FC<CertificationDetailsSidebarProps> = (props
                 )}
             </ul>
 
-            <div className={classNames('body-main-medium', styles['section-header'])}>
+            <div className={classNames('body-small-medium', styles['section-header'])}>
                 Skills Covered
             </div>
             <ul className={styles['certification-skills-list']}>