Apply automatic rubocop fixes

spec/helpers/admin/dashboard_helper_spec.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require 'rails_helper'
 
 describe Admin::DashboardHelper do
@@ -8,7 +10,7 @@ describe Admin::DashboardHelper do
   end
 
   describe '#docker_data' do
-    before(:each) { FactoryBot.create(:ruby) }
+    before { FactoryBot.create(:ruby) }
 
     it 'contains an entry for every execution environment' do
       expect(docker_data.length).to eq(ExecutionEnvironment.count)

spec/helpers/application_helper_spec.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require 'rails_helper'
 
 describe ApplicationHelper do

spec/helpers/exercise_helper_spec.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require 'rails_helper'
 
 describe ExerciseHelper do

spec/helpers/yaml_spec.rb

@@ -5,7 +5,7 @@ require 'yaml'
 
 describe 'yaml config files' do
   Find.find(__dir__, 'config') do |path|
-    next unless path =~ /.*.\.yml/
+    next unless /.*.\.yml/.match?(path)
 
     it "loads #{path} without syntax error" do
       expect { YAML.load_file(path) }.not_to raise_error