fix(CNavGroup): add the missing href attribute to the toggler

Author: mrholek

packages/coreui-react/src/components/nav/CNavGroup.tsx

@@ -124,7 +124,11 @@ export const CNavGroup: PolymorphicRefForwardingComponent<'li', CNavGroupProps>
       ref={ref}
     >
       {toggler && (
-        <a className="nav-link nav-group-toggle" onClick={(event) => handleTogglerOnCLick(event)}>
+        <a
+          className="nav-link nav-group-toggle"
+          href="#"
+          onClick={(event) => handleTogglerOnCLick(event)}
+        >
           {toggler}
         </a>
       )}