Correct invalid table markup

- Add required <tr> within <thead>
  - Add implicit <tbody> after <thead>

spec/features/event_types_spec.rb

@@ -13,7 +13,7 @@ feature EventType do
       visit admin_conference_program_event_types_path(
                 conference_id: conference.short_title)
 
-      within('table#event_types') do
+      within('table#event_types > tbody') do
         expect(page.assert_selector('tr', count: 2)).to be true
       end
 
@@ -30,7 +30,7 @@ feature EventType do
       page.find('#flash')
       # Validations
       expect(flash).to eq('Event type successfully created.')
-      within('table#event_types') do
+      within('table#event_types > tbody') do
         expect(page.has_content?('Party')).to be true
         expect(page.has_content?('13042')).to be true
         expect(page.has_content?('#E4E4E4')).to be true
@@ -44,7 +44,7 @@ feature EventType do
       page.find('#flash')
       expect(flash).to eq('Event type successfully deleted.')
 
-      within('table#event_types') do
+      within('table#event_types > tbody') do
         expect(page.assert_selector('tr', count: 2)).to be true
         expect(page.has_content?('Party')).to be false
       end

spec/features/roles_spec.rb

@@ -127,7 +127,7 @@ feature Role do
       scenario 'successfully removes role organization_admin' do
         click_link('Admins', href: admins_admin_organization_path(organization.id))
 
-        first('tr').find('.btn-danger').click
+        first('tbody > tr').find('.btn-danger').click
         organization_admin.reload
         expect(organization_admin.has_cached_role?('organization_admin', organization)).to be false
       end