List of speakers: 'add me'/point of order Button is visible, even if user doesn't have permission

[MSoeb]

Describe the bug
The 'Add me' and the point of order button in the list of speakers is always visible, even though users do not have permission to add themselves to the list of speakers. This leads to the error message 'Error: You are not allowed to perform action speaker.create. Missing Permission: list_of_speakers.can_be_speaker'.

How to Reproduce
Steps to reproduce the behavior:

1. open a meeting
2. open agenda > create an item
3. open participants > create a user A as delegate with the permission to see the list of speakers
4. project the agenda item
5. login as user A, open the Autopilot > you will see the 'add me' button and you can click it > error appears

Expected behavior
If users ONLY have the permission to see the list of speakers, the 'Add me' and point of order button should NOT be visible.

Only with the permission 'Can put oneself on the list of speakers' can users see these buttons and put themselves on the list of speakers.