Bump rubocop-rails from 2.18.0 to 2.20.2

Bumps [rubocop-rails](https://github.com/rubocop/rubocop-rails) from 2.18.0 to 2.20.2.
- [Release notes](https://github.com/rubocop/rubocop-rails/releases)
- [Changelog](https://github.com/rubocop/rubocop-rails/blob/master/CHANGELOG.md)
- [Commits](rubocop/rubocop-rails@v2.18.0...v2.20.2)

---
updated-dependencies:
- dependency-name: rubocop-rails
  dependency-type: direct:development
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <[email protected]>

Gemfile

@@ -67,7 +67,7 @@ group :development, :ci, :test do
   gem 'table_print', '~> 1.5', '>= 1.5.6' # giuNice table printing of data for the console
   gem 'colorize', '~> 0.8.1' # Print colorized text in debugger/console
   gem 'rubocop', '~> 1.48.1'
-  gem 'rubocop-rails', '~> 2.18'
+  gem 'rubocop-rails', '~> 2.20'
   gem 'rubocop-rake', '~> 0.6.0'
   gem 'rubocop-rspec', '~> 2.19'
   gem 'shoulda-matchers', '~> 5.3.0'

Gemfile.lock

@@ -288,9 +288,10 @@ GEM
       mini_portile2 (~> 2.8.2)
       racc (~> 1.4)
     orm_adapter (0.5.0)
-    parallel (1.22.1)
-    parser (3.2.2.0)
+    parallel (1.23.0)
+    parser (3.2.2.3)
       ast (~> 2.4.1)
+      racc
     pg (1.4.6)
     power_assert (2.0.3)
     premailer (1.18.0)
@@ -358,7 +359,7 @@ GEM
       rails (>= 5.2)
       rainbow (~> 3.0)
       webpacker (>= 4.2)
-    regexp_parser (2.7.0)
+    regexp_parser (2.8.1)
     reline (0.3.3)
       io-console (~> 0.5)
     request_store (1.5.1)
@@ -404,11 +405,11 @@ GEM
       rubocop-ast (>= 1.26.0, < 2.0)
       ruby-progressbar (~> 1.7)
       unicode-display_width (>= 2.4.0, < 3.0)
-    rubocop-ast (1.28.0)
+    rubocop-ast (1.29.0)
       parser (>= 3.2.1.0)
     rubocop-capybara (2.17.1)
       rubocop (~> 1.41)
-    rubocop-rails (2.18.0)
+    rubocop-rails (2.20.2)
       activesupport (>= 4.2.0)
       rack (>= 1.1)
       rubocop (>= 1.33.0, < 2.0)
@@ -542,7 +543,7 @@ DEPENDENCIES
   rspec-json_expectations (~> 2)
   rspec-rails (~> 4.1.2)
   rubocop (~> 1.48.1)
-  rubocop-rails (~> 2.18)
+  rubocop-rails (~> 2.20)
   rubocop-rake (~> 0.6.0)
   rubocop-rspec (~> 2.19)
   sassc (~> 2.0, >= 2.0.1)