Switch GalacticSearchPath to pi2

We've been using pi2, not pi1

Change-Id: I10105b51c761a61eb22d2b5bf31933ff7e312d0b
diff --git a/y2020/actors/autonomous_actor.cc b/y2020/actors/autonomous_actor.cc
index d3d8570..92cb7cb 100644
--- a/y2020/actors/autonomous_actor.cc
+++ b/y2020/actors/autonomous_actor.cc
@@ -40,7 +40,7 @@
       joystick_state_fetcher_(
           event_loop->MakeFetcher<aos::JoystickState>("/aos")),
       path_fetcher_(event_loop->MakeFetcher<y2020::vision::GalacticSearchPath>(
-          "/pi1/camera")),
+          "/pi2/camera")),
       auto_splines_() {
   set_max_drivetrain_voltage(2.0);
 }