Embed SVG using `custom_icon`

app/views/projects/builds/show.html.haml

@@ -56,13 +56,18 @@
       - else
         #js-build-scroll.scroll-controls
           .scroll-step
-            %a{ href: '#up-build-trace', id: 'scroll-top', class: 'scroll-link scroll-top', title: 'Scroll to top'}
-            %a{ href: '#down-build-trace', id: 'scroll-bottom', class: 'scroll-link scroll-bottom', title: 'Scroll to bottom'}
+            %a{ href: '#up-build-trace', id: 'scroll-top', class: 'scroll-link scroll-top', title: 'Scroll to top' }
+              = custom_icon('scroll_up')
+              = custom_icon('scroll_up_hover_active')
+            %a{ href: '#down-build-trace', id: 'scroll-bottom', class: 'scroll-link scroll-bottom', title: 'Scroll to bottom' }
+              = custom_icon('scroll_down')
+              = custom_icon('scroll_down_hover_active')
           - if @build.active?
             .autoscroll-container
               %span.status-message#autoscroll-status{ data: { state: 'disabled' } }
                 %span.status-text Autoscroll active
                 %i.status-icon
+                  = custom_icon('scroll_down_hover_active')
         #up-build-trace
         %pre.build-trace#build-trace
           %code.bash.js-build-output