Change the upper bound to match the lower bound

This causes the red light to stop when in gets to the last key, rather than continuing on
past the end of the array before turning around.

src/Kaleidoscope-LEDEffect-Chase.cpp

@@ -10,7 +10,7 @@ void LEDChaseEffect::update(void) {
   ::LEDControl.setCrgbAt(pos, {0, 0, 0});
 
   pos += chase_sign;
-  if (pos >= LED_COUNT || pos <= 0) {
+  if (pos >= (LED_COUNT - 1) || pos <= 0) {
     chase_sign = -chase_sign;
   }
   ::LEDControl.setCrgbAt(pos, {0, 0, 255});