Bump rubocop-rspec from ~> 2.27.0 to ~> 2.27.1

This should bust the gems cache and cause us to update from
rubocop-rspec 2.27.0 to 2.27.1 for CI runs.

Gemfile

@@ -13,7 +13,7 @@ gem 'rake', '~> 13.0'
 gem 'rspec', '~> 3.7'
 gem 'rubocop-performance', '~> 1.20.0'
 gem 'rubocop-rake', '~> 0.6.0'
-gem 'rubocop-rspec', '~> 2.27.0'
+gem 'rubocop-rspec', '~> 2.27.1'
 # Workaround for cc-test-reporter with SimpleCov 0.18.
 # Stop upgrading SimpleCov until the following issue will be resolved.
 # https://github.com/codeclimate/test-reporter/issues/418