Group Migration - Show import status - frontend

Problem description

Per this comment, we are currently using an inefficient workaround to show the status of any group import in progress. This current solution does not make a distinction between certain states, i.e. Pending and Running.

Proposed solution

Take advantage of the new API solution that allows for accurate and efficient status display.

Illustrations

The UI mockups can be found here: #271505 (closed)