Adding individual user permissions for the Questions app will not work

Issue Summary

To allow users to interact with the Confluence Questions app (such as upvoting and accepting an answer), the user and the Confluence Questions app account should be added to the space permissions.

 The user and groups that will allow the account to interact with it should be added to the Add-on tab under the Permissions configuration of the space as well.

If the app's account is already added to the space permissions and then, under the Add-on tab, the user account is added individually to the permissions (not via groups), the user will still not be able to interact with the answers.

Steps to Reproduce

1. In a Confluence instance that has Confluence Questions installed, access a space.
2. Go to the space permissions via Space settings > Permissions and select the Add-on tab.
3. Add the user individually to the permissions, granting all of them:
   
4. Have the user trying to upvote or accept an answer.

Expected Results

As the user has permission granted, the account should be able to accept or upvote the answer.

Actual Results

The user is not able to upvote or accept an answer and the following messages will be displayed:

Accept answer didn't work

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Unauthorized action
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Workaround

Add the user's group to the Add-on permissions tab for Questions.