update capybara specs for subscription toggle

spec/features/boards/sidebar_spec.rb

@@ -334,14 +334,14 @@ describe 'Issue Boards', :js do
       wait_for_requests
 
       page.within('.subscriptions') do
-        click_button 'Subscribe'
+        find('.js-issuable-subscribe-button button:not(.is-checked)').click
         wait_for_requests
 
-        expect(page).to have_content('Unsubscribe')
+        expect(page).to have_css('.js-issuable-subscribe-button button.is-checked')
       end
     end
 
-    it 'has "Unsubscribe" button when already subscribed' do
+    it 'has checked subscription toggle when already subscribed' do
       create(:subscription, user: user, project: project, subscribable: issue2, subscribed: true)
       visit project_board_path(project, board)
       wait_for_requests
@@ -350,10 +350,10 @@ describe 'Issue Boards', :js do
       wait_for_requests
 
       page.within('.subscriptions') do
-        click_button 'Unsubscribe'
+        find('.js-issuable-subscribe-button button.is-checked').click
         wait_for_requests
 
-        expect(page).to have_content('Subscribe')
+        expect(page).to have_css('.js-issuable-subscribe-button button:not(.is-checked)')
       end
     end
   end

spec/features/projects/merge_requests/user_manages_subscription_spec.rb

@@ -13,20 +13,18 @@ describe 'User manages subscription', :js do
   end
 
   it 'toggles subscription' do
-    subscribe_button = find('.js-issuable-subscribe-button')
-
-    expect(subscribe_button).to have_content('Subscribe')
-
-    click_on('Subscribe')
+    page.within('.js-issuable-subscribe-button') do
+      expect(page).to have_css 'button:not(.is-checked)'
+      find('button:not(.is-checked)').click
 
       wait_for_requests
 
-    expect(subscribe_button).to have_content('Unsubscribe')
-
-    click_on('Unsubscribe')
+      expect(page).to have_css 'button.is-checked'
+      find('button.is-checked').click
 
       wait_for_requests
 
-    expect(subscribe_button).to have_content('Subscribe')
+      expect(page).to have_css 'button:not(.is-checked)'
+    end
   end
 end