Calendar - Can't remove invited user from events

• Type: Regression Bug
• Status: Closed
• Resolution: Fixed
• Affects Version/s: 7.0.X, 7.1.X, 7.2.10 DXP FP1, 7.2.X, Master
• Fix Version/s: 7.1.X, 7.2.X, 7.3.0 CE GA1, 7.3.1 CE GA2, 7.3.10 DXP GA1, Master
• Component/s: Calendar
• Labels: None
• Branch Version/s:
  7.2.x, 7.1.x
• Backported to Branch:
  Committed
• Fix Priority: 4
• Git Pull Request: https://github.com/brianchandotcom/liferay-portal/pull/80404

Steps to reproduce:
1. Control Panel > Users > Users and Organizations > Add User
2. Fill in required fields and Save.
3. Return to the homepage > Click the Add button > Search and Add a Calendar portlet
4. Click "Add Event" button.
5. In the "Invitations" input, invite the new user that was created > Publish
6. Scroll down to the Invited user > Click the down arrow > Click Remove > Publish
7. Scroll down to see removed user is still on the list.

Expected outcome:
User is removed from the event.

Actual outcome:
User is still in the list of people invited to the event.

Produced on:
Master -

Commit: bde67ee189e438bb57d8ceef095e82cf9e423fad
Base Branch Commit: 0357af11a67c63a5a937a2fb8024d5ba7e132cdb