Fix tests for FeedController

And remove useless Fallbacks in Fallback controller

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

lib/mobilizon_web/controllers/fallback_controller.ex

@@ -6,20 +6,6 @@ defmodule MobilizonWeb.FallbackController do
   """
   use MobilizonWeb, :controller
 
-  def call(conn, {:error, %Ecto.Changeset{} = changeset}) do
-    conn
-    |> put_status(:unprocessable_entity)
-    |> put_view(MobilizonWeb.ChangesetView)
-    |> render("error.json", changeset: changeset)
-  end
-
-  def call(conn, {:error, nil}) do
-    conn
-    |> put_status(:unprocessable_entity)
-    |> put_view(MobilizonWeb.ErrorView)
-    |> render("invalid_request.json")
-  end
-
   def call(conn, {:error, :not_found}) do
     conn
     |> put_status(:not_found)