fix(a11y): hide dumbbell icon from screen readers (freeCodeCamp#60884)

Author: igor570

client/src/assets/icons/dumbbell.tsx

@@ -4,6 +4,7 @@ function DumbbellIcon(
 ): JSX.Element {
   return (
     <svg
+      aria-hidden='true'
       xmlns='http://www.w3.org/2000/svg'
       width='62'
       height='55'