Stop the ball a bit more when preloading

We've seen a couple of balls trapped past the sensor and jammed into the
roller.  We aren't seeing them too short, so up the limit.

Change-Id: I7e1e11317f69496ed3791127cf3fb682dcc8e802
Signed-off-by: Austin Schuh <austin.linux@gmail.com>
diff --git a/y2020/control_loops/superstructure/superstructure.h b/y2020/control_loops/superstructure/superstructure.h
index 3eb6cb2..07b7575 100644
--- a/y2020/control_loops/superstructure/superstructure.h
+++ b/y2020/control_loops/superstructure/superstructure.h
@@ -32,7 +32,7 @@
   static constexpr std::chrono::milliseconds kPreloadingTimeout =
       std::chrono::seconds(2);
   static constexpr std::chrono::milliseconds kPreloadingBackpowerDuration =
-      std::chrono::milliseconds(50);
+      std::chrono::milliseconds(55);
 
   using PotAndAbsoluteEncoderSubsystem =
       ::frc971::control_loops::StaticZeroingSingleDOFProfiledSubsystem<