Rename Uploading label to Processing for file attachments

This is to match the behaviour implemented for images.

It can be confusing when the label reads uploading, but the user
may already be able to see and use the original asset. This helps
clarify that some background processing is still ongoing.

app/views/admin/attachments/_attachments.html.erb

@@ -7,7 +7,7 @@
     <li class="govuk-grid-row">
       <div class="govuk-grid-column-full">
         <p class="govuk-body">
-          <strong>Title:</strong> <%= attachment.title %> <% unless attachment.attachment_data.blank? || attachment.attachment_data.all_asset_variants_uploaded? %><span class="govuk-tag govuk-tag--green">Uploading</span><% end %>
+          <strong>Title:</strong> <%= attachment.title %> <% unless attachment.attachment_data.blank? || attachment.attachment_data.all_asset_variants_uploaded? %><span class="govuk-tag govuk-tag--green">Processing</span><% end %>
         </p>
         <p class="govuk-body">
           <strong>Type: </strong><%= attachment.is_a?(HtmlAttachment) ? attachment.readable_type : attachment.readable_type.capitalize %>

features/step_definitions/attachment_steps.rb

@@ -70,7 +70,7 @@
 end
 
 Then(/^the attachments should be in the following order:$/) do |attachment_list|
-  attachment_names = all("li p:first").map(&:text).map { |t| t.delete_prefix("Title:").chomp("Uploading").strip }
+  attachment_names = all("li p:first").map(&:text).map { |t| t.delete_prefix("Title:").chomp("Processing").strip }
 
   attachment_list.hashes.each_with_index do |attachment_info, index|
     attachment = Attachment.find_by(title: attachment_info[:title])

features/step_definitions/consultation_steps.rb

@@ -94,7 +94,7 @@
 end
 
 Then(/^the responses attachments should be in the following order:$/) do |attachment_list|
-  attachment_names = all("li p:first").map(&:text).map { |t| t.delete_prefix("Title:").chomp("Uploading").strip }
+  attachment_names = all("li p:first").map(&:text).map { |t| t.delete_prefix("Title:").chomp("Processing").strip }
 
   attachment_list.hashes.each_with_index do |attachment_info, index|
     attachment = Attachment.find_by(title: attachment_info[:title])

test/functional/admin/attachments_controller_test.rb

@@ -111,7 +111,7 @@ def self.supported_attachable_types
     assert_response :success
     assert_select "p.govuk-body", text: "Title: An HTML attachment"
     assert_select "p.govuk-body", text: "Title: An uploaded file attachment"
-    assert_select "p.govuk-body", text: "Title: An uploading file attachment Uploading"
+    assert_select "p.govuk-body", text: "Title: An uploading file attachment Processing"
     assert_select "p.govuk-body", text: "Title: An external attachment"
   end