Simplify creation of empty json array

Co-Authored-By: Samantaz Fox <coding@samantaz.fr>

src/invidious/channels/community.cr

@@ -61,10 +61,7 @@ def extract_channel_community(items, *, ucid, locale, format, thin_mode, is_sing
       response = JSON.build do |json|
         json.object do
           json.field "authorId", ucid
-          json.field "comments" do
+          json.field "comments", json.array { }
-            json.array do
-            end
-          end
         end
       end
       return response