Problems displaying users in audit log #2863

Describe the bug
In the audit log, although I can search for a user, I cannot select them to view their audit trail - I can only see the audit trail for users who are visible in the dropdown list (20 users). When I click on the user name I have searched for, the user name reverts to 'No user selected', or the last user selected that was in the dropdown list

Steps To Reproduce
Steps to reproduce the behavior:

1. Go to Settings', 'Audit Log'
2. Set an event filter
3. Click on 'User'
4. Type user name in search box
5. Click on desired user name
6. See error

Expected behavior
That when I search for a user it should allow me to select them (even if they aren't in the default dropdown list) and see their audit trail.

Screenshots
User selected from dropdown (ok):

Search for user:

Click user name (returns to no user or last selected user):

Your Configuration (please complete the following information):

• Exact BookStack Version (Found in settings): BookStack v21.05.3
• PHP Version: 8.0.8
• Hosting Method (Nginx/Apache/Docker): Apache
• Linux: Ubuntu 20.04.2 LTS

Additional context
The 20 users in the dropdown list are the LAST 20 users in the application (in this case names beginning Z to N).