MastodonAPI search: return only create activities.

lib/pleroma/web/mastodon_api/mastodon_api_controller.ex

@@ -494,6 +494,10 @@ def search(%{assigns: %{user: user}} = conn, %{"q" => query} = params) do
       if Regex.match?(~r/https?:/, query) do
         with {:ok, activities} <- OStatus.fetch_activity_from_url(query) do
           activities
+          |> Enum.filter(fn
+            %{data: %{"type" => "Create"}} -> true
+            _ -> false
+          end)
         else
           _e -> []
         end