This rule was added in rubocop-rspec 2.9.0.
We were using `be_nil` 50% of the time, and `be nil` the rest of the
time. No strong preference for either one, but IMHO we don't lose
anything be being consistent.
We introduced this bug in commit 55d339572, since we didn't take hidden
records into consideration.
I've tried to use `update_column` to simplify the code, but got a syntax
error `unnamed portal parameter` and didn't find how to fix it.