Introduce group posts

Signed-off-by: Thomas Citharel <tcit@tcit.fr>

lib/federation/activity_stream/converter/picture.ex

@@ -39,7 +39,7 @@ defmodule Mobilizon.Federation.ActivityStream.Converter.Picture do
         actor_id
       )
       when is_bitstring(picture_url) do
-    with {:ok, %HTTPoison.Response{body: body}} <- HTTPoison.get(picture_url, [], @http_options),
+    with {:ok, %{body: body}} <- Tesla.get(picture_url, opts: @http_options),
          {:ok, %{name: name, url: url, content_type: content_type, size: size}} <-
            Upload.store(%{body: body, name: name}),
          {:picture_exists, nil} <- {:picture_exists, Media.get_picture_by_url(url)} do