Merge branch '534_federation_targets_reachability' into 'develop'

[#534] Unreachable federation targets retirement

Closes #534

See merge request pleroma/pleroma!703

test/support/http_request_mock.ex

@@ -696,6 +696,14 @@ defmodule HttpRequestMock do
     {:ok, %Tesla.Env{status: 200, body: "hello"}}
   end
 
+  def get("http://404.site" <> _, _, _, _) do
+    {:ok,
+     %Tesla.Env{
+       status: 404,
+       body: ""
+     }}
+  end
+
   def get(url, query, body, headers) do
     {:error,
      "Not implemented the mock response for get #{inspect(url)}, #{query}, #{inspect(body)}, #{
@@ -716,6 +724,26 @@ defmodule HttpRequestMock do
      }}
   end
 
+  def post("http://200.site" <> _, _, _, _) do
+    {:ok,
+     %Tesla.Env{
+       status: 200,
+       body: ""
+     }}
+  end
+
+  def post("http://connrefused.site" <> _, _, _, _) do
+    {:error, :connrefused}
+  end
+
+  def post("http://404.site" <> _, _, _, _) do
+    {:ok,
+     %Tesla.Env{
+       status: 404,
+       body: ""
+     }}
+  end
+
   def post(url, _query, _body, _headers) do
     {:error, "Not implemented the mock response for post #{inspect(url)}"}
   end