Not catching this error can apparently result in the client just
repeatedly sending the same request over and over. It is unclear if
handling this improves the situation.

[24-Aug-2024 16:39:03.294221]: [ERR] {"user":"service@example.com","cmd":"MeetingResponse","device":"4D0259F81B9042959AC5BF0C7B895496","type":"WindowsOutlook15"} Syncroton_Server::_handlePost::170 unexpected exception occured: Syncroton_Exception_Status
[24-Aug-2024 16:39:03.294304]: [ERR] {"user":"service@example.com","cmd":"MeetingResponse","device":"4D0259F81B9042959AC5BF0C7B895496","type":"WindowsOutlook15"} Syncroton_Server::_handlePost::173 exception message: Unknown server error
[24-Aug-2024 16:39:03.294367]: [ERR] {"user":"service@example.com","cmd":"MeetingResponse","device":"4D0259F81B9042959AC5BF0C7B895496","type":"WindowsOutlook15"} Syncroton_Server::_handlePost::176 #0 /usr/share/kolab-syncroton/lib/kolab_sync_data.php(713): kolab_sync_storage->getItem('38b950ebd62cd9a...', '4D0259F81B90429...', 'event', '38b950ebd62cd9a...')
#1 /usr/share/kolab-syncroton/lib/kolab_sync_data_calendar.php(909): kolab_sync_data->getObject('38b950ebd62cd9a...', '38b950ebd62cd9a...')
#2 /usr/share/kolab-syncroton/lib/kolab_sync_data_calendar.php(694): kolab_sync_data_calendar->get_event_from_invitation(Object(Syncroton_Model_MeetingResponse))
#3 /usr/share/kolab-syncroton/lib/ext/Syncroton/Command/MeetingResponse.php(40): kolab_sync_data_calendar->setAttendeeStatus(Object(Syncroton_Model_MeetingResponse))
#4 /usr/share/kolab-syncroton/lib/ext/Syncroton/Server.php(149): Syncroton_Command_MeetingResponse->handle()
#5 /usr/share/kolab-syncroton/lib/ext/Syncroton/Server.php(71): Syncroton_Server->_handlePost()
#6 /usr/share/kolab-syncroton/lib/kolab_sync.php(178): Syncroton_Server->handle()
#7 /usr/share/kolab-syncroton/index.php(31): kolab_sync->run()
#8 {main}