add alt text to thumbnails

Author: Smullz622

app/components/thumbnail_component.html.erb

@@ -1,7 +1,7 @@
 <div class="<%= html_classes %>">
   <% if display_thumbnail? %>
-    <img src="<%= thumbnail_url %>" class="bordered-thumbnail-image" alt="">
+    <img src="<%= thumbnail_url %>" class="bordered-thumbnail-image" alt="Thumbnail image for <%= resource.title %>">
   <% else %>
-    <i class='material-icons material-icons--thumbnail'><%= icon %></i>
+    <i class='material-icons material-icons--thumbnail' alt="Default thumbnail image for <%= resource.title %>"><%= icon %></i>
   <% end %>
 </div>

spec/features/resources_spec.rb

@@ -313,6 +313,7 @@
         it 'displays the thumbnail' do
           expect(page).to have_css("img[src='url.com/path/file']")
           expect(page).to have_css('.thumbnail-card')
+          expect(page).to have_css("img[alt='Thumbnail image for #{work.title}']")
         end
       end
     end
@@ -439,6 +440,7 @@
         it 'displays the thumbnail' do
           expect(page).to have_css("img[src='url.com/path/file']")
           expect(page).to have_css('.thumbnail-card')
+          expect(page).to have_css("img[alt='Thumbnail image for #{collection.title}']")
         end
       end
     end