FEATURE: add full editing access to queued posts (#5047)

For pending new topics: the body of the post, title, categories
and the tags are editable.

For pending new replies: only the body is applicable and thus
editable

DISCUSSION: https://meta.discourse.org/t/66754

spec/fabricators/queued_post_fabricator.rb

@@ -15,3 +15,12 @@ Fabricator(:queued_post) do
       image_sizes: { "http://foo.bar/image.png" => { "width" => 0, "height" => 222 } } }
   end
 end
+
+Fabricator(:queued_topic, from: :queued_post) do
+  topic nil
+  raw 'This post should be queued up, and more importantly, this is a new topic'
+  post_options do
+    { category: 1,
+      title: 'This is a new topic' }
+  end
+end