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.
Note we're excluding a few files:
* Configuration files that weren't generated by us
* Migration files that weren't generated by us
* The Gemfile, since it includes an important comment that must be on
the same line as the gem declaration
* The Budget::Stats class, since the heading statistics are a mess and
having shorter lines would require a lot of refactoring
We were very inconsistent regarding these rules.
Personally I prefer no empty lines around blocks, clases, etc... as
recommended by the Ruby style guide [1], and they're the default values
in rubocop, so those are the settings I'm applying.
The exception is the `private` access modifier, since we were leaving
empty lines around it most of the time. That's the default rubocop rule
as well. Personally I don't have a strong preference about this one.
[1] https://rubystyle.guide/#empty-lines-around-bodies
