Fix Style/HashSyntax violations

spec/features/issues_spec.rb

@@ -295,7 +295,7 @@ describe 'Issues', feature: true do
         issue.save
       end
 
-      it 'allows user to remove assignee', :js => true do
+      it 'allows user to remove assignee', js: true do
         visit namespace_project_issue_path(project.namespace, project, issue)
         expect(page).to have_content "Assignee: #{user2.name}"
 

spec/helpers/preferences_helper_spec.rb

@@ -61,7 +61,7 @@ describe PreferencesHelper do
       (1..5).each do |color_scheme_id|
         context "with color_scheme_id == #{color_scheme_id}" do
           it 'should return a string' do
-            current_user = double(:color_scheme_id => color_scheme_id)
+            current_user = double(color_scheme_id: color_scheme_id)
             allow(self).to receive(:current_user).and_return(current_user)
             expect(user_color_scheme_class).to be_kind_of(String)
           end

spec/support/db_cleaner.rb

@@ -25,7 +25,7 @@ RSpec.configure do |config|
     DatabaseCleaner.strategy = :transaction
   end
 
-  config.before(:each, :js => true) do
+  config.before(:each, js: true) do
     DatabaseCleaner.strategy = :truncation
   end