Challenge Listings - Search : Must have a X button to clear search

Describe the bug The challenge search input must have a X button to clear the search

To Reproduce Steps to reproduce the behavior:

1. go to challenge listing page
2. type any keyword in the search box and click on search button
3. challenge list is updated to show search results

Actual: There is no x button to clear the search. The user either has to delete the search keyword and search again or use clear filter button to clear the search

Expected: There should be a X button to clear the search.

Please make PR against https://github.com/topcoder-platform/community-app/tree/hot-fix-x-button-to-clear-search

Final Submission Guidelines

Git issue link: https://github.com/topcoder-platform/community-app/issues/3622