Active group member not found when adding enrollees to event

Problem/Motivation

When we try to enroll users to a group, the user is not found in the select field.

Steps to reproduce

1. Search for group member in select2 field on page /node/{ID}/all-enrollments/add-enrollees
2. User who is an active group member is not found

Proposed resolution

Loading enrollments with status = 1 in SocialEventManagersAddEnrolleeForm.php#L178

Remaining tasks

Discuss the patch if it breaks functionality.

This issue applies to version 11.11.4, but the behavior is the same with latest 13.x.