Merge branch 'clipboard-button-styling' into 'master'

Fixed styling of clipboard button

Closes #18773 

See merge request !4728

app/helpers/button_helper.rb

@@ -17,7 +17,7 @@ module ButtonHelper
   def clipboard_button(data = {})
     content_tag :button,
       icon('clipboard'),
-      class: "btn",
+      class: "btn btn-clipboard",
       data: data,
       type: :button
   end