Fix inconsistent use of #check_for helper in SignalException
Fix inconsistent use of #check_for helper in SignalException

When the enforced style is `semantic`, `check_for(:raise, ...)` meant that we
*don't* want to see `raise`. But with other styles, `check_for(:raise, ...)`
meant that we *do* want to see `raise`.

Make the usage consistent.

jonas054/rubocop,jonas054/rubocop