Fix service calls on root page

When the root page (/) loads, we show the Active Challenges tab selected and the list of all challenges for the logged in user, across all projects.

This works, but it makes too many requests to the services. Tested in Firefox on macOS Catalina.

Note - this should be fixed for all 3 tabs :

• Active
• Draft
• Completed

Issue 1

I'm seeing duplicate calls to the same endpoint with the same parameters. This shouldn't happen.

Issue 2

We're not paginating in the table properly - we're just loading the first two pages and displaying the results. Instead, we should add pagination controls to the table and only load the first "chunk" of challenges when the page first loads, allowing the user to paginate. Pagination should work with or without a search term filter.

Final Submission Guidelines

Git issue link: https://github.com/topcoder-platform/challenge-engine-ui/issues/171