Check unsafe-expect false positives

[matiascabello]

In the precision evaluation, several unsafe-expect issues were marked as false positives. Check if any refining in the detector is possible to avoid the issue being triggered in those scenarios.

Reference: https://docs.google.com/spreadsheets/d/1a7yfwU206FeSToDt74d-l6gSzhO9IYih6LK6e-07Ajo/edit?gid=848561478#gid=848561478