Bump rubocop-rails from 2.8.1 to 2.9.1 (#11924) [deploy]

Bumps [rubocop-rails](https://github.com/rubocop-hq/rubocop-rails) from 2.8.1 to 2.9.1.
- [Release notes](https://github.com/rubocop-hq/rubocop-rails/releases)
- [Changelog](https://github.com/rubocop-hq/rubocop-rails/blob/master/CHANGELOG.md)
- [Commits](https://github.com/rubocop-hq/rubocop-rails/compare/v2.8.1...v2.9.1)

Signed-off-by: dependabot[bot] <support@github.com>

Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Gemfile

@@ -140,7 +140,7 @@ group :development, :test do
   gem "rspec-rails", "~> 4.0" # rspec-rails is a testing framework for Rails 3+
   gem "rubocop", "~> 0.93.1", require: false # Automatic Ruby code style checking tool
   gem "rubocop-performance", "~> 1.9", require: false # A collection of RuboCop cops to check for performance optimizations in Ruby code
-  gem "rubocop-rails", "~> 2.8", require: false # Automatic Rails code style checking tool
+  gem "rubocop-rails", "~> 2.9", require: false # Automatic Rails code style checking tool
   gem "rubocop-rspec", "~> 1.44", require: false # Code style checking for RSpec files
   gem "spring", "~> 2.1" # Preloads your application so things like console, rake and tests run faster
   gem "spring-commands-rspec", "~> 1.0" # rspec command for spring

Gemfile.lock

@@ -639,15 +639,15 @@ GEM
       rubocop-ast (>= 0.6.0)
       ruby-progressbar (~> 1.7)
       unicode-display_width (>= 1.4.0, < 2.0)
-    rubocop-ast (1.2.0)
+    rubocop-ast (1.3.0)
       parser (>= 2.7.1.5)
     rubocop-performance (1.9.1)
       rubocop (>= 0.90.0, < 2.0)
       rubocop-ast (>= 0.4.0)
-    rubocop-rails (2.8.1)
+    rubocop-rails (2.9.1)
       activesupport (>= 4.2.0)
       rack (>= 1.1)
-      rubocop (>= 0.87.0)
+      rubocop (>= 0.90.0, < 2.0)
     rubocop-rspec (1.44.1)
       rubocop (~> 0.87)
       rubocop-ast (>= 0.7.1)
@@ -925,7 +925,7 @@ DEPENDENCIES
   rspec-retry (~> 0.6)
   rubocop (~> 0.93.1)
   rubocop-performance (~> 1.9)
-  rubocop-rails (~> 2.8)
+  rubocop-rails (~> 2.9)
   rubocop-rspec (~> 1.44)
   ruby-prof (~> 1.4)
   rubyzip (~> 2.3)