[$15] Number of registrants does not count the actual number of users correctly

[LieutenantRoger]

1. go to any new challenge details page and register for the challenge.

2. Within few seconds, the user will be listed under the registrations column, but the number of registrants does not get updated

3. As you can see in the below image, there are 5 registrants but the number shows only 4
   

4. Although this gets updated properly after a refresh

[LieutenantRoger]

Challenge https://www.topcoder.com/challenges/9b28feda-3f3f-4913-9f4e-3201315fab87 has been created for this ticket.

This is an automated message for lieutenantroger via Topcoder X

[nqviet]

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[bug-bash-helper]

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