Merge branch 'fix-arduino-robots-link'

Author: PeterJCLaw

content/api/arduino.md

@@ -27,7 +27,7 @@ The first few digital pins are occupied by digital inputs, the next few by
 digital outputs, and the analogue pins are attached to ultrasound sensors.
 
 To find out how many inputs and outputs each type of robot has, check the
-[robot docs](../../robots).
+[robot docs](../../robots/).
 
 You won't be able to change pin mode like in
 a physical robot (see below), but pins 0 and 1 are still unavailable.