fix(masthead-search): no redirect when search input empty (#3939)

### Related Ticket(s)

React version fix of #3932

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packages/react/src/components/Masthead/MastheadSearch.js

@@ -224,7 +224,7 @@ const MastheadSearch = ({
    *
    */
   function searchIconClick() {
-    if (state.isSearchOpen) {
+    if (state.isSearchOpen && state.val.length) {
       root.parent.location.href = getRedirect(state.val);
     } else {
       dispatch({ type: 'setSearchOpen' });