Preloading: Fix nodeinfo url.

lib/pleroma/web/preload/instance.ex

@@ -10,7 +10,7 @@ defmodule Pleroma.Web.Preload.Providers.Instance do
   @behaviour Provider
   @instance_url :"/api/v1/instance"
   @panel_url :"/instance/panel.html"
-  @nodeinfo_url :"/nodeinfo/2.0"
+  @nodeinfo_url :"/nodeinfo/2.0.json"
 
   @impl Provider
   def generate_terms(_params) do

test/web/preload/instance_test.exs

@@ -25,7 +25,7 @@ test "it renders the panel", %{"/instance/panel.html": panel} do
            )
   end
 
-  test "it renders the node_info", %{"/nodeinfo/2.0": nodeinfo} do
+  test "it renders the node_info", %{"/nodeinfo/2.0.json": nodeinfo} do
     %{
       metadata: metadata,
       version: "2.0"