Make Move activity federate properly

Ref: emit-move

lib/pleroma/web/activity_pub/activity_pub.ex

@@ -416,7 +416,8 @@ def move(%User{} = origin, %User{} = target, local \\ true) do
       "type" => "Move",
       "actor" => origin.ap_id,
       "object" => origin.ap_id,
-      "target" => target.ap_id
+      "target" => target.ap_id,
+      "to" => [origin.follower_address]
     }
 
     with true <- origin.ap_id in target.also_known_as,

test/pleroma/web/activity_pub/activity_pub_test.exs

@@ -1739,9 +1739,12 @@ test "create" do
                  "target" => ^new_ap_id,
                  "type" => "Move"
                },
-               local: true
+               local: true,
+               recipients: recipients
              } = activity
 
+      assert old_user.follower_address in recipients
+
       params = %{
         "op" => "move_following",
         "origin_id" => old_user.id,