The counter on the Group membership is not working

Problem/Motivation

When we select members on the Manage members page counter of selected members are not changed. It's because of updates in the JS of the new version of the VBO module.

Steps to reproduce

Go to the group Manage members page
Select any user
The counter is not changed

Proposed resolution

Update response in custom callback (SocialCoreController::updateSelection) to take into account changes in the VBO module.