Update Coveralls handling for GitHub actions

.github/workflows/ci.yml

@@ -14,6 +14,9 @@ jobs:
           ruby-version: ${{ matrix.ruby }}
       - run: bundle install
       - run: bundle exec rspec
+      - uses: coverallsapp/github-action@master
+        with:
+          github-token: ${{ secrets.GITHUB_TOKEN }}
   rubocop:
     name: RuboCop
     runs-on: ubuntu-latest

Gemfile

@@ -5,5 +5,5 @@ source 'https://rubygems.org'
 gemspec
 
 group :test do
-  gem 'coveralls', '~> 0.6'
+  gem 'simplecov-lcov'
 end

spec/support/simplecov.rb

@@ -3,8 +3,14 @@
 require 'simplecov'
 
 if ENV['CI']
-  require 'coveralls'
-  SimpleCov.formatter = Coveralls::SimpleCov::Formatter
+  require 'simplecov-lcov'
+
+  SimpleCov::Formatter::LcovFormatter.config do |config|
+    config.report_with_single_file = true
+    config.single_report_path = 'coverage/lcov.info'
+  end
+
+  SimpleCov.formatter = SimpleCov::Formatter::LcovFormatter
 end
 
 SimpleCov.start do