Apply suggestions from code review

Co-authored-by: Bo Anderson <[email protected]>

Library/Homebrew/hardware.rb

@@ -98,7 +98,7 @@ def family
  :dunno
  end
 
- sig { returns(T.nilable(Integer)) }
+ sig { returns(Integer) }
  def cores
  return @cores if @cores
 
@@ -178,12 +178,12 @@ def virtualized?
  false
  end
 
- sig { returns(T::Array[String]) }
+ sig { returns(T::Array[Symbol]) }
  def features
  []
  end
 
- sig { params(name: T::Array[String]).returns(T::Boolean) }
+ sig { params(name: Symbol).returns(T::Boolean) }
  def feature?(name)
  features.include?(name)
  end
@@ -203,7 +203,7 @@ def in_rosetta2?
  end
 
  class << self
- sig { returns(T.nilable(T.any(Integer, String))) }
+ sig { returns(String) }
  def cores_as_words
  case Hardware::CPU.cores
  when 1 then "single"