Prior to SERVER-67905, AdmissionContext::_startProcessingTime was initialized as follows 

TickSource::Tick _startProcessingTime{}; 

Now, it is initialized as 

TickSource::Tick _startProcessingTime{0};

We should check if initializing the TicketSource tick to 0 instead of its default {} means the _startProcessingTime computed for ticketHolders will spit unrealistic values when the ticketHolder is resized. 

Example: TicketHolderWithQueueingStats::resize() calls TicketHolderWithQueueingStats::_release() with an AdmissionContext defined on the stack that never has its _startProcessingTime initialized to a non-zero value before it is used to compute the _totalTimeProcessingMicros