Coverity found a Security issue: Overflowed constant

Details:

Coverity Issue ID: 185227
Issue Description: Integer overflow occurs in arithmetic on constant operands
Potential Impact: The overflowed value due to arithmetic on constants is too small or unexpectedly negative, causing incorrect computations.
Coverity checker: INTEGER_OVERFLOW
Branch: master
File path: /src/mongo/db/exec/agg/change_stream_unwind_transaction_stage.h
Line number: Unknown

What Coverity Detected (Main Finding)

Expression "this->_currentApplyOpsIndex - 1UL", where "this->_currentApplyOpsIndex" is known to be equal to 0, underflows the type of "this->_currentApplyOpsIndex - 1UL", which is type "unsigned long".

The issue can be viewed in Coverity here.

How do I fix this?

Refer to https://wiki.corp.mongodb.com/spaces/HGTC/pages/385852267/Guidance+on+fixing+Coverity+issues for guidance on fixing Coverity issues.

This is a false positive, what do I do?

Follow the process outlined in go/vuln-flow